Does synthetic motor oil cause seal leaks on newer cars?
alan
I'm considering changing over to synthetic motor oil on my 60,000 mile car.
It is a 97 Civic and the previous owner changed the oil (Castrol GTX) every
3700 miles and drove mostly highway miles. I'll mostly be using this car
for short trips and city driving. I figured that synthetic will help in the
stop and go city driving because less oil will burn if the engine gets hot.
As for the short trips, I think the issue is with water condensing and
forming acids. I am not convinced of the reasons, but I believe that
synthetic is a little better about this because it has/creates less
(combustion?) byproducts that can react with the water to form acids.
Anyway, the main thing I am worried about is the seals leaking, especially
the one that leads into the clutch (rear seal?). I have heard that
synthetic can cause seals to shrink (at least back in the old days) but to
what extent is this still true today? Also, I believe it is still true that
synthetic can "unplug" a leak that was already there, but sealed up with
gunk from the conventional oil. I guess I just have to have faith that the
seals on my car are still good? Or is there a way to tell? As far as I
know, my car does not currently have any oil leaks. Thanks for any advice
ACF
Dean Dardwin
Here we go again! Synthetic oil DOES NOT cause leaks, period. You may
notice one more benefit of synthetic oil, better gas mileage.
Dean
alan
"Dean Dardwin" <d...@dxd.com> wrote in message
news:3C45635F...@dxd.com...
Dean Dardwin
Dean
mrdancer
news:a23li5$djo$1...@usenet.Stanford.EDU...
Some of the poor-quality synthetic oils may cause seals to shrink, just as
some poor-quality synthetic oils may cause seals to actually swell. It all
depends on the mix of ingredients in the oil base (I use to know them, but
forgot, and too lazy to look it up right now).
Buy a quality synthetic (not a blend) such as Mobil 1 or Amsoil, and you
won't have to worry about your seals.
When I switched to synthetic (0w30) in my truck, oil consumption actually
went DOWN (from a quart every 3k to a quart every 5k).
--
Remove .your.underwear to reply
--
Bob Snow
years and have never used or lost oil in any car using synthetic. Only
exception was a 77 Rabbit with bad valve guide seals, but that happened to
all of them and was fixed in a recall.
Kensei
As has been posted, it does not cause seals to leak. What it will do
is seep through spaces that regular oil would not leak through....
giving the impression that it's negatively effecting the seals.
Hence, a car MAY leak more going from regular to synthetic oil but
it's not due to seal damage.
Kensei
C. E. White
>
> Alan,
>
> Here we go again! Synthetic oil DOES NOT cause leaks, period. You may
> notice one more benefit of synthetic oil, better gas mileage.
I agree that modern synthetic oil doesn't cause seals to leak. I don't
agree that it will improve gas mileage enough to be noticeable. I own
three vehicles. In two of the three I have tried both synthetic and
conventional oils (Havoline 5W30 conventional, Mobil 1 5W30 Synthetic).
I keep very careful gas mileage records. There is essentially no
difference in my mileage related to the two types of oil. In one of my
vehicles (1997 Ford Expedition) I used synthetic oil for over 60,000
miles and conventional oil for over 60,000 miles. The average fuel
mileage for the two types of oil was within .01 mpg (14.09 mpg for
62,524 miles using Havoline 5W30, 14.08 mpg for 63,678 miles using Mobil
1 5W30).
I think there are some very good reasons for using synthetic oil in some
applications. However, don't fool yourself into thinking you are going
to get significantly greater gas mileage compared to a similar grade of
good quality conventional oil. For most people, using synthetic oil is
like putting powdered sugar on top of a cream filled chocolate covered
donut. You might think you want it, but it probably isn't doing you any
good.
Regards,
Ed White
Dean Dardwin
Dean
Robert Snow
supposed to improve some performance factor. People are always claiming new
spark plugs give them noticeably increased performance or mileage.
I think that synthetic oil has some real benefits though. It flows better
when cold. It does not break down as badly from extreme high temperature. It
does seem to keep the engine cleaner because it's less like to contribute to
deposits from breaking down. Fewer additives are needed to extend the
viscosity range. I change my Mobil 1 at 10k and I would not be comfortable
doing that with conventional oil. It saves me a lot of work with three cars
to maintain.
Kevin McMurtrie
"alan" <acf...@yahoo.do_not_spam_me.com> wrote:
It's not a problem on a 97 model. The seals are still good as new.
When a car nears 10 years of age the seals become brittle as clay.
Solvents, different blends of oil, or a different driving pattern can
change the seal's normal swelling. Any change in swelling can cause the
seal to crumble a little earlier than it normally would.
If I recall correctly, timing belt maintenance often includes the front
crankshaft seal and a clutch replacement sometimes includes the rear
crankshaft seal. The camshaft seals and valve cover seals can be done
at home or at a gas station. The valve stem seals are a pain but can be
done at home or by a competant mechanic. If you get the crankshaft
seals replaced along with normal maintenance, there's not too much to
worry about when 2007 comes along.
David Brodbeck
"Robert Snow" <rsn...@home.com> wrote in message
news:B86B5C23.579C%rsn...@home.com...
> I think the placebo effect is very strong when people buy a product that
is
> supposed to improve some performance factor. People are always claiming
new
> spark plugs give them noticeably increased performance or mileage.
From observing audiophile newsgroups I think the strength of the placebo
effect is directly related to the cost of the item.
Kent Finnell
"David Brodbeck" <dbro...@ameritech.net> wrote in message
news:5yp18.3423$75.24...@newssvr28.news.prodigy.com...
ago and there has been NO mileage improvement. Any power gains would be
purely subjective and marginal at best. The Si does seem to pull a little
more smoothly from low rpms, but again, that's subjective.
--
Kent Finnell
From the Music City, USA
George Macdonald
>Alan,
>
>Here we go again! Synthetic oil DOES NOT cause leaks, period. You may
>notice one more benefit of synthetic oil, better gas mileage.
Synthetic oil *has* had problems with seal leakage in the past - this is
*not* myth. This has been mitigated by additives which compensate for the
solvent action on the seals and improved seal materials. There is also no
doubt that changing to synthetic oil on an older engine which has seen
nothing but petroleum based lubricant can flush out some of the false
sealing built up over the miles/years.
The question is at what mileage and time does the change become a risk.
60K miles *might* be OK but then again it may depend on unknown factors and
*some* "synthetics" are no longer really synthetic anyway. Any change in
the "solvent" which comes into contact with seals can obviously affect them
in one way or another, causing increased swelling or shrinkage. The fact
that the previous owner changed his GTX regularly may improve the chances
of success here but then again, a leaking rear seal is no fun.
Rgds, George Macdonald
"Just because they're paranoid doesn't mean you're not psychotic" - Who, me??
CBB
fammacd=!SPAM^noth...@garden.net (George Macdonald) wrote:
> On Wed, 16 Jan 2002 05:26:23 -0600, Dean Dardwin <d...@dxd.com> wrote:
>
> >Alan,
> >
> >Here we go again! Synthetic oil DOES NOT cause leaks, period. You may
> >notice one more benefit of synthetic oil, better gas mileage.
>
> Synthetic oil *has* had problems with seal leakage in the past - this is
> *not* myth. This has been mitigated by additives which compensate for the
> solvent action on the seals and improved seal materials. There is also no
> doubt that changing to synthetic oil on an older engine which has seen
> nothing but petroleum based lubricant can flush out some of the false
> sealing built up over the miles/years.
>
> The question is at what mileage and time does the change become a risk.
> 60K miles *might* be OK but then again it may depend on unknown factors and
> *some* "synthetics" are no longer really synthetic anyway. Any change in
> the "solvent" which comes into contact with seals can obviously affect them
> in one way or another, causing increased swelling or shrinkage. The fact
> that the previous owner changed his GTX regularly may improve the chances
> of success here but then again, a leaking rear seal is no fun.
>
I switched to full synthetic for the first time at about 90 kmiles, just
to give it a try. Next morning, oil spots on my garage floor. Never had
a single drip before that. This continued with just a few drops each
night until I switched back to conventional oil and then it stopped
completely. Semi-synthetic doesn't seem to cause a problem though.
CBB
z
I've used Mobil 1 since just about the beginning with my 92 Civic,
didn't leak (my previous Mitsubishi developed valve cover leaks I
never could seal with synthetic). But I didn't change the front main
seal when I changed the timing belt, and it started to leak a few
months later. For one change I tried that Valvoline Maxlife that has
extra seal swelling goop, that stopped the leak, I changed back to
Mobil 1 to see what happened, and it's been OK still (3 months).
Change that front main seal when you do the timing belt! And change
the rear main seal when you change the clutch, even though you have to
pull the flywheel to get to it (I would guess).
Dean Dardwin
I agree with your conclusion but not how you got there. I have used
Mobil 1 in engines built in the '50s through today. This includes cars,
trucks, farm tractors, lawn mowers, power plants, log splitters, garden
tillers, string trimmers, and so forth. None of them has ever leaked one
drop of Mobil 1. All have their original seals. Of course, I maintained
them properly with high quality detergent oils in the days before Mobil
1 was available. When I made the switch, some of the truck engines had
well over 100k miles; the farm tractor was a '68 model with over 10,000
hours on the original engine. Nope, seals haven't changed. What has
changed is that some people used poor maintenance practices (cheap oil
not changed appropriately) and then when they made the switch to
synthetic is was just convenient to blame the oil for removing the
"false seals" as you correctly pointed out.. My experience, and that of
most folks who use synthetics, has been nothing but very positive.
Dean
George Macdonald
>George,
>
>I agree with your conclusion but not how you got there. I have used
>Mobil 1 in engines built in the '50s through today. This includes cars,
>trucks, farm tractors, lawn mowers, power plants, log splitters, garden
>tillers, string trimmers, and so forth. None of them has ever leaked one
>drop of Mobil 1. All have their original seals. Of course, I maintained
>them properly with high quality detergent oils in the days before Mobil
>1 was available. When I made the switch, some of the truck engines had
>well over 100k miles; the farm tractor was a '68 model with over 10,000
>hours on the original engine. Nope, seals haven't changed. What has
>changed is that some people used poor maintenance practices (cheap oil
>not changed appropriately) and then when they made the switch to
>synthetic is was just convenient to blame the oil for removing the
>"false seals" as you correctly pointed out.. My experience, and that of
>most folks who use synthetics, has been nothing but very positive.
Disagree with the facts if you will. The seal material has to be the
correct formula as does the oil to avoid leaks. Over the years Mobil has
modified the formula to improve its compatibility with seal materials,
including the addition of a dibasic ester plasticizer... which is also a
lubricant. The false seal issue has nothing to do with poor maintenance
practice - it's simply a case of changing the solvent (the oil) which comes
in contact with the sealing surface.
Robert Snow
and Mobil 1 back in the late seventies. I believe they were dealt with by
the early eighties. I forget the viscosity rating, but I also remember the
original formulation was a very light weight oil.
My dad had a 1965 Plymouth Sport Fury. He never maintained any of his cars.
He bought them used and added oil as needed. Never had it changed. I
remember changing the oil in that car, after I got a 68 Mustang and started
to learn about maintenance. It was really dirty and thick when it came out.
I put in new conventional oil and it just leaked from everywhere after that.
Eventually the carburetor went and the car got slower and slower and then he
sold it. He just waxed the hood, no joke, because that's what he saw when he
drove it.
Dean Dardwin
False seals have everything to do with poor maintenance. Here's how it works. Non detergent oils and any oil not changed in a timely fashion allow acids to build up in the crankcase. These acids eat seals. The oil that seeps around the seals carries the accumulated "crud" to the gaps and eventually forms a false seal. These can remain in place for many years and not leak a drop. As soon as the false seal gets dissolved (kerosene, synthetic oil), a leak develops. This is not conjecture on my part. I've been rebuilding engines since the '60s. I've seen many times. I'll bet every old-timer mechanic knows exactly what I'm talking about!
Dean
Sean Dinh
years ago. There are no oil leakage problems.
George Macdonald
>I read in some Mobil technical papers that there were problems with seals
>and Mobil 1 back in the late seventies. I believe they were dealt with by
>the early eighties. I forget the viscosity rating, but I also remember the
>original formulation was a very light weight oil.
>
>My dad had a 1965 Plymouth Sport Fury. He never maintained any of his cars.
>He bought them used and added oil as needed. Never had it changed. I
>remember changing the oil in that car, after I got a 68 Mustang and started
>to learn about maintenance. It was really dirty and thick when it came out.
>I put in new conventional oil and it just leaked from everywhere after that.
>Eventually the carburetor went and the car got slower and slower and then he
>sold it. He just waxed the hood, no joke, because that's what he saw when he
>drove it.
Yeah there are lots of funny stories. I remember a college friend scoffing
at my suggestion that he change his engine oil - according to him it was a
petroleum industry con job which he refused to subscribe to: "nah, ya just
top it up when it needs it". I also remember my sister, who had a similar
philosophy, having trouble with her car and taking it to my father to "look
at". He checked the dipstick level - seemed fine, so he then took the
engine oil drain plug off and nothing came out. Next he took it to a
mechanic he knew well who dropped the oil pan and found what "looked like a
lump of liver" in there.
George Macdonald
>
>--------------070902090807010006010101
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>George,
>
>False seals have everything to do with poor maintenance. Here's how it
>works. Non detergent oils and any oil not changed in a timely fashion
>allow acids to build up in the crankcase. These acids eat seals.
No it's not the acids that eat seals - in fact the seal materials are quite
impervious to the common acids likely to be found in an engine. All motor
oils have been high detergent for >40 years - non-detergents are still
available for the few applications that require them of course.
> The oil
>that seeps around the seals carries the accumulated "crud" to the gaps
>and eventually forms a false seal. These can remain in place for many
>years and not leak a drop. As soon as the false seal gets dissolved
>(kerosene, synthetic oil), a leak develops. This is not conjecture on
>my part. I've been rebuilding engines since the '60s. I've seen many
>times. I'll bet every old-timer mechanic knows exactly what I'm talking
>about!
The principle ingredient in Mobil1 is (was?) polyalphaolefin (PAO) which
has a different solvent action on seals than say a mineral based oil. In
fact alone, PAO will leach out some of the plasticizer from many seal
materials rendering them less flexible. Ideally the oil which comes into
contact with the seal should cause a small amount of swelling of the seal
material for the best/longest life performance.
Obviously seal materials were originally chosen with mineral based
lubricants in mind though there is some evidence that latterly, their
composition has been changed somewhat to better accomodate the various
synthetic oils. I wish I knew the details better but I don't - suffice it
to say that the ratio of BUNA and Nitrile, e.g., rubber in a seal material
for satisfactory performance with various oils is now well understood.
The lubricant mfrs have also responded to the situation by including the
plasticizer I previously mentioned as part of their formula - diisodecyl
adipate is one used by Valvoline in their Synpower. Now even if the
synthetic oil is "compatible" with current seal materials it does not mean
that it is compatible with a seal which has been "conditioned" by
years/miles of contact with mineral based oil, whether that conditioning
includes accumulated crud or not. Depending on the exact seal material,
the mineral based oil used, the change to a synthetic oil *can* lead to
degradation of the seal material resulting in leakage.
Of course non of the above rules out the possibility of a seal which only
works based on accumulated crud from improper maintenance and which ceases
to work properly when that crud is flushed away by the cleansing action of
the synthetic oil. IOW there's more than one possible scenario here.
>George Macdonald wrote:
>
>>On Thu, 17 Jan 2002 15:57:52 -0600, Dean Dardwin <d...@dxd.com> wrote:
>>
>>>George,
>>>
>>>I agree with your conclusion but not how you got there. I have used
>>>Mobil 1 in engines built in the '50s through today. This includes cars,
>>>trucks, farm tractors, lawn mowers, power plants, log splitters, garden
>>>tillers, string trimmers, and so forth. None of them has ever leaked one
>>>drop of Mobil 1. All have their original seals. Of course, I maintained
>>>them properly with high quality detergent oils in the days before Mobil
>>>1 was available. When I made the switch, some of the truck engines had
>>>well over 100k miles; the farm tractor was a '68 model with over 10,000
>>>hours on the original engine. Nope, seals haven't changed. What has
>>>changed is that some people used poor maintenance practices (cheap oil
>>>not changed appropriately) and then when they made the switch to
>>>synthetic is was just convenient to blame the oil for removing the
>>>"false seals" as you correctly pointed out.. My experience, and that of
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>
><html>
><head>
></head>
><body>
>George,<br>
><br>
>False seals have everything to do with poor maintenance. Here's how it works.
>Non detergent oils and any oil not changed in a timely fashion allow acids
>to build up in the crankcase. These acids eat seals. The oil that seeps around
>the seals carries the accumulated "crud" to the gaps and eventually forms
>a false seal. These can remain in place for many years and not leak a drop.
>As soon as the false seal gets dissolved (kerosene, synthetic oil), a leak
>develops. This is not conjecture on my part. I've been rebuilding engines
>since the '60s. I've seen many times. I'll bet every old-timer mechanic knows
>exactly what I'm talking about!<br>
><br>
>Dean<br>
><br>
>George Macdonald wrote:<br>
><blockquote type="cite" cite="mid:3c48fb15...@news.garden.net">
> <pre wrap="">On Thu, 17 Jan 2002 15:57:52 -0600, Dean Dardwin <a class="moz-txt-link-rfc2396E" href="mailto:d...@dxd.com"><d...@dxd.com></a> wrote:<br><br></pre>
> <blockquote type="cite">
> <pre wrap="">George,<br><br>I agree with your conclusion but not how you got there. I have used <br>Mobil 1 in engines built in the '50s through today. This includes cars, <br>trucks, farm tractors, lawn mowers, power plants, log splitters, garden <br>tillers, string trimmers, and so forth. None of them has ever leaked one <br>drop of Mobil 1. All have their original seals. Of course, I maintained <br>them properly with high quality detergent oils in the days before Mobil <br>1 was available. When I made the switch, some of the truck engines had <br>well over 100k miles; the farm tractor was a '68 model with over 10,000 <br>hours on the original engine. Nope, seals haven't changed. What has <br>changed is that some people used poor maintenance practices (cheap oil <br>not changed appropriately) and then when they made the switch to <br>synthetic is was just convenient to blame the oil for removing the <br>"false seals" as you correctly pointed out.. My experience, and th
>at of <br>most folks who use synthetics, has been nothing but very positive.<br></pre>
> </blockquote>
> <pre wrap=""><!----><br>Disagree with the facts if you will. The seal material has to be the<br>correct formula as does the oil to avoid leaks. Over the years Mobil has<br>modified the formula to improve its compatibility with seal materials,<br>including the addition of a dibasic ester plasticizer... which is also a<br>lubricant. The false seal issue has nothing to do with poor maintenance<br>practice - it's simply a case of changing the solvent (the oil) which comes<br>in contact with the sealing surface.<br><br></pre>
> <blockquote type="cite">
> <pre wrap="">George Macdonald wrote:<br><br></pre>
> <blockquote type="cite">
> <pre wrap="">On Wed, 16 Jan 2002 05:26:23 -0600, Dean Dardwin <a class="moz-txt-link-rfc2396E" href="mailto:d...@dxd.com"><d...@dxd.com></a> wrote:<br><br></pre>
> <blockquote type="cite">
> <pre wrap="">Alan,<br><br>Here we go again! Synthetic oil DOES NOT cause leaks, period. You may <br>notice one more benefit of synthetic oil, better gas mileage.<br><br></pre>
> </blockquote>
> <pre wrap="">Synthetic oil *has* had problems with seal leakage in the past - this is<br>*not* myth. This has been mitigated by additives which compensate for the<br>solvent action on the seals and improved seal materials. There is also no<br>doubt that changing to synthetic oil on an older engine which has seen<br>nothing but petroleum based lubricant can flush out some of the false<br>sealing built up over the miles/years.<br><br>The question is at what mileage and time does the change become a risk.<br>60K miles *might* be OK but then again it may depend on unknown factors and<br>*some* "synthetics" are no longer really synthetic anyway. Any change in<br>the "solvent" which comes into contact with seals can obviously affect them<br>in one way or another, causing increased swelling or shrinkage. The fact<br>that the previous owner changed his GTX regularly may improve the chances<br>of success here but then again, a leaking rear seal is no fun.<br><br></pre>
> <blockquote type="cite">
> <pre wrap="">Dean<br><br>alan wrote:<br><br></pre>
> <blockquote type="cite">
> <pre wrap="">Hello people,<br><br>I'm considering changing over to synthetic motor oil on my 60,000 mile car.<br>It is a 97 Civic and the previous owner changed the oil (Castrol GTX) every<br>3700 miles and drove mostly highway miles. I'll mostly be using this car<br>for short trips and city driving. I figured that synthetic will help in the<br>stop and go city driving because less oil will burn if the engine gets hot.<br>As for the short trips, I think the issue is with water condensing and<br>forming acids. I am not convinced of the reasons, but I believe that<br>synthetic is a little better about this because it has/creates less<br>(combustion?) byproducts that can react with the water to form acids.<br><br>Anyway, the main thing I am worried about is the seals leaking, especially<br>the one that leads into the clutch (rear seal?). I have heard that<br>synthetic can cause seals to shrink (at least back in the old days) but to<br>what extent is this still
> true today? Also, I believe it is still true that<br>synthetic can "unplug" a leak that was already there, but sealed up with<br>gunk from the conventional oil. I guess I just have to have faith that the<br>seals on my car are still good? Or is there a way to tell? As far as I<br>know, my car does not currently have any oil leaks. Thanks for any advice<br><br>ACF<br></pre>
> </blockquote>
> </blockquote>
> </blockquote>
> </blockquote>
> <pre wrap=""><!----><br>Rgds, George Macdonald<br><br>"Just because they're paranoid doesn't mean you're not psychotic" - Who, me??<br></pre>
> </blockquote>
> <br>
> </body>
> </html>
>
>--------------070902090807010006010101--
Dean Dardwin
The lubricant mfrs have also responded to the situation by including the
plasticizer I previously mentioned as part of their formula - diisodecyl
adipate is one used by Valvoline in their Synpower. Now even if the
synthetic oil is "compatible" with current seal materials it does not mean
that it is compatible with a seal which has been "conditioned" by
years/miles of contact with mineral based oil, whether that conditioning
includes accumulated crud or not. Depending on the exact seal material,
the mineral based oil used, the change to a synthetic oil *can* lead to
degradation of the seal material resulting in leakage.
Of course non of the above rules out the possibility of a seal which only
works based on accumulated crud from improper maintenance and which ceases
to work properly when that crud is flushed away by the cleansing action of
the synthetic oil. IOW there's more than one possible scenario here.
George Macdonald wrote:
On Thu, 17 Jan 2002 15:57:52 -0600, Dean Dardwin <d...@dxd.com> wrote:
George,
I agree with your conclusion but not how you got there. I have used
Mobil 1 in engines built in the '50s through today. This includes cars,
trucks, farm tractors, lawn mowers, power plants, log splitters, garden
tillers, string trimmers, and so forth. None of them has ever leaked one
drop of Mobil 1. All have their original seals. Of course, I maintained
them properly with high quality detergent oils in the days before Mobil
1 was available. When I made the switch, some of the truck engines had
well over 100k miles; the farm tractor was a '68 model with over 10,000
hours on the original engine. Nope, seals haven't changed. What has
changed is that some people used poor maintenance practices (cheap oil
not changed appropriately) and then when they made the switch to
synthetic is was just convenient to blame the oil for removing the
"false seals" as you correctly pointed out.. My expe rience, and that of
George Macdonald wrote:
of success here but then again, a leaking rear seal is no fun.< br>
George Macdonald
>
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>Content-Transfer-Encoding: quoted-printable
Could you please quit posting in HTML - it makes a mess and is a huge waste
of bandwidth on Usenet.
>
>George Macdonald wrote:
>
>>On Sat, 19 Jan 2002 07:02:00 -0600, Dean Dardwin <d...@dxd.com> wrote:
>>
>>>--------------070902090807010006010101
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>>>
>>>George,
>>>
>>>False seals have everything to do with poor maintenance. Here's how it =
>
>>>works. Non detergent oils and any oil not changed in a timely fashion=20
>>>allow acids to build up in the crankcase. These acids eat seals.
>>>
>>
>>No it's not the acids that eat seals - in fact the seal materials are qu=
>ite
>>impervious to the common acids likely to be found in an engine. All mot=
>or
>>oils have been high detergent for >40 years - non-detergents are still
>>available for the few applications that require them of course.
>>
>>>The oil=20
>>>that seeps around the seals carries the accumulated "crud" to the gaps =
>
>>>and eventually forms a false seal. These can remain in place for many=20
>>>years and not leak a drop. As soon as the false seal gets dissolved=20
>>>(kerosene, synthetic oil), a leak develops. This is not conjecture on =
>
>>>my part. I've been rebuilding engines since the '60s. I've seen many=20
>>>times. I'll bet every old-timer mechanic knows exactly what I'm talking=
>=20
>>>about!
>>>
>>
>>The principle ingredient in Mobil1 is (was?) polyalphaolefin (PAO) which=
>
>>has a different solvent action on seals than say a mineral based oil. I=
>n
>>fact alone, PAO will leach out some of the plasticizer from many seal
>>materials rendering them less flexible. Ideally the oil which comes int=
>o
>>contact with the seal should cause a small amount of swelling of the sea=
>l
>>material for the best/longest life performance.
>>
>>Obviously seal materials were originally chosen with mineral based
>>lubricants in mind though there is some evidence that latterly, their
>>composition has been changed somewhat to better accomodate the various
>>synthetic oils. I wish I knew the details better but I don't - suffice =
>it
>>to say that the ratio of BUNA and Nitrile, e.g., rubber in a seal materi=
>al
>>for satisfactory performance with various oils is now well understood.
>>
>
>Seal materials from 40 years ago were damaged (dried out, as it were) by =
>
>long term exposure to acids present in the crankcase as a result of=20
>blowby. Modern seals were not improved to deal with synthetic oils (they =
>
>have only become popular in the last 20 years or so). They were improved =
>
>as part of basic materials research and adopted for automotive use due=20
>to their ability to deal with crankcase acids and heat, among other thing=
>s.
I'd suggest you do some research on lubricants in general, synthetics in
particular and their recommended seal materials.
>>
>>
>>The lubricant mfrs have also responded to the situation by including the=
>
>>plasticizer I previously mentioned as part of their formula - diisodecyl=
>
>>adipate is one used by Valvoline in their Synpower. Now even if the
>>synthetic oil is "compatible" with current seal materials it does not me=
>an
>>that it is compatible with a seal which has been "conditioned" by
>>years/miles of contact with mineral based oil, whether that conditioning=
>
>>includes accumulated crud or not. Depending on the exact seal material,=
>
>>the mineral based oil used, the change to a synthetic oil *can* lead to
>>degradation of the seal material resulting in leakage.
>>
>
>Given that you can construct any number of combinations of materials and =
>
>conditions regarding modern engines using modern seals and assert that=20
>some bizarre circumstance can lead to leaking, I'll just assert the fact =
>
>that literally millions of high-mile engines using modern seals have=20
>been converted from conventional oil to synthetic oil without developing =
>
>any leaks whatsoever.
Nothing bizarre is going on here - these are the facts of chemistry - and
many other people have had leaks develop when switching to synthetic oil
after following good maintenance practices.
TobyU
mad and switch back....
I have had high mile vehicles leak a few drops after synthetic and much more
common,,I have had them USE a bunch on the first syn change or two.
After the third or so change, it is all back to normal.
"George Macdonald" <fammacd=!SPAM^noth...@garden.net> wrote in message
news:3c4f5d62...@news.garden.net...
mrdancer
miles, my oil consumption went from a quart every 3000 miles to a quart
every 5000 miles.
Yup, it used LESS oil w/ synthetic, even though it was a lighter weight.
--
Remove .your.underwear to reply
--
"TobyU" <tunde...@woh.rr.com> wrote in message
news:BBL38.44543$yy3.8...@typhoon.neo.rr.com...
ryan r.
but i chose the best (royal purple). i immediately noticed a
difference in the pitch and gas mileage, and best of all no leaks
anywhere. my car runs great now.
Robert Snow
gas mileage or change in pitch of the engine. I have noticed that after many
thousands of miles, whenever I take the cover off the camshaft to adjust
valves, there are no depsoits and everything looks like new. I think there
is less wear, mainly due to the ability of synthetic oil to flow well in
very cold weather. I think things are cleaner because it has fewer
impurities to break down. I don't ever seem to loose compression or oil
pressure in any engines running synthetic.
I hear so many people claim that sparkplugs, airfilters, oil and such make
noticeable improvements in gas mileage and horsepower. I've never seen it. I
am just happy if the car runs like it did when it was new during the second
100,000 miles.
Paul
> I've used Mobil 1 for more than 20years. I have never noticed an
> increase in gas mileage or change in pitch of the engine. I have
> noticed that after many thousands of miles, whenever I take the cover
> off the camshaft to adjust valves, there are no depsoits and everything
> looks like new. I think there is less wear, mainly due to the ability
> of synthetic oil to flow well in very cold weather. I think things are
> cleaner because it has fewer impurities to break down. I don't ever
> seem to loose compression or oil pressure in any engines running
> synthetic.
Maybe the reason you haven't noticed these 2 oberservations is because you
were already using sythentic oil. I made the switch after about the first 2
oil changes and did notice an improvement in cold starting ability and
sound and gas mileage. BTW, I use Mobil 1 exclusively also.
Bror Jace
> i have a 96 honda civic with and at 100,000 i change to synth. oil,
> but i chose the best (royal purple).
The best? Says who? That stuff isn't even 100% synthetic.
i immediately noticed a
> difference in the pitch and gas mileage, and best of all no leaks
> anywhere. my car runs great now.
You probably might have noticed a change if you used ANY synthetic or
synthetic blend ... especially if you wanted to. Good luck with the
car but I would find a better synthetic oil or stick with dino SL and
use 3,000 drain intervals.
--- Bror Jace
CarBiz
I like the synthetic, but not on cars that either leak some or have over
100k on them.
I've tested this personally in my lab and the viscosity and molecular
dependency of the two types and the results support this.
"C. E. White" <cewh...@mindspring.com> wrote in message
news:3C45C731...@mindspring.com...
Bror Jace
> ago and there has been NO mileage improvement. Any power gains would be
> purely subjective and marginal at best. The Si does seem to pull a little
> more smoothly from low rpms, but again, that's subjective.
I switched from a mixture of Valvoline Synpower 5W30 and 10W30 to Red
Line 10W30 ... and my mileage actually DROPPED significantly (2-3mpg).
I attribute this to the fact that Red Line actually seems thicker than
its equivalent weight in mass-market synthetics.
I switched to Red Line 5W30 and when summer comes around again, I'll
see if I can't get those 2mpg back.
--- Bror Jace
Bror Jace
George,
This Dibasic Ester Plasticizer you mention as one part of the new
Mobil 1 Triumverate, exactly what is this stuff? It SOUNDS like it
could be called synthetic … polymers and plastics should fit
just about anyone’s definition of that word. BUT, is it GOOD
stuff? STP is a polymer and I wouldn’t say that it is really
good stuff, especially not for something that is going to be pushed
hard … meaning high heat and high RPMs. My faith in STP was
dashed several years ago when I used a 75/25 mixture of 20W50oil and
STP in an air-cooled 3-wheeler. It didn’t take too much use
before this mixture would run off the dipstick like water when the
engine got warm.
I heard from someone who called Havoline and their synthetic formula
is also a PAO/ ester blend … same answer I got when I talked to
an Amsoil booster on another forum.
How good is this plasticizer as a lubricant? How about thermal
stability?
Another forum participant posted their oil analysis after using Mobil
1 for only 5,000 miles in a 2-year old 5.7L Chevy pickup . Their TBN
was only between 2.0 and 3.0, they had high lead and a few other
troubling trace elements. Imagine of this supposed super-premium oil
was used in a car that recommends extended drain intervals twice that
length and longer? >:^O
Oh, and if you call "1 800 ask mobil" they will tell you that the
formula is still primarily PAO.
--- Bror Jace
mrdancer
"Bror Jace" <bror...@hotmail.com> wrote in message
news:d1373663.02012...@posting.google.com...
> I heard from someone who called Havoline and their synthetic formula
> is also a PAO/ ester blend … same answer I got when I talked to
> an Amsoil booster on another forum.
IIRC, you always want a blend of PAO/ester bases. If you have no blend,
just one or the other, then you could have problems with seal
shrinkage/swelling (I forget which base does which). This is why some of
the early (and cheaper) synthetics caused seal problems, which consequently
led to stories that are perpetuated as truth in modern times.
The actual blend ratio of PAO/ester bases is a closely guarded secret among
oil companies - each has their own proprietary blend.
George Macdonald
If you look up the MSDS for Valvoline's Dordrecht Synpower 0W/30 or 0W/40
you'll see that they still show as containing 1%-10% diisodecyl adipate, a
dibasic ester. A search at Google on "diisodecyl adipate" will turn up
quite a bit of info, basically showng that it's a plasticizer *and* a
lubricant. Some of the synthetic lubricants for cars like Redline etc.
which were inspired by the jet engine lubricants are supposedly principally
ester based polymers and dibasic esters. I'm not sure what the exact
chemical compounds are there but there is evidently some similarity in the
chemical makeup.
> STP is a polymer and I wouldn’t say that it is really
>good stuff, especially not for something that is going to be pushed
>hard … meaning high heat and high RPMs. My faith in STP was
>dashed several years ago when I used a 75/25 mixture of 20W50oil and
>STP in an air-cooled 3-wheeler. It didn’t take too much use
>before this mixture would run off the dipstick like water when the
>engine got warm.
AFAIK STP is basically just a VI improver with some other additives to
control foaming and emulsification plus some zinc dialkyldithiophosphate -
IOW it basically contains more of the additives which are already in most
lubricants and is not a particularly good lubricant.
>I heard from someone who called Havoline and their synthetic formula
>is also a PAO/ ester blend … same answer I got when I talked to
>an Amsoil booster on another forum.
Yeah well when I asked Castrol about Syntec about a year ago through their
Web-based e-mail form, they replied that it was PAO - IOW they lied. I
thought that Amsoil was one of those which came from the ester polymer jet
engine lube inspired route.
>How good is this plasticizer as a lubricant? How about thermal
>stability?
I have to say I've never seen the stuff but AFAIK it is a good lubricant -
since it is a plasticizer, alone it would tend to cause cause excessive
seal swelling. The ester based compounds have a reputation for good
thermal stability but it'd certainly be worth looking up diisodecyl adipate
again to see if there is a spec on that.
>Another forum participant posted their oil analysis after using Mobil
>1 for only 5,000 miles in a 2-year old 5.7L Chevy pickup . Their TBN
>was only between 2.0 and 3.0, they had high lead and a few other
>troubling trace elements. Imagine of this supposed super-premium oil
>was used in a car that recommends extended drain intervals twice that
>length and longer? >:^O
Do you have numbers on analyses on other experiences with other lubricants
to compare with here?
>Oh, and if you call "1 800 ask mobil" they will tell you that the
>formula is still primarily PAO.
Makes you wonder.:-) At least Valvoline is not being coy about the change
to hydrocracked basestocks.
George Macdonald
>I've used Mobil 1 for more than 20years. I have never noticed an increase in
>gas mileage or change in pitch of the engine. I have noticed that after many
>thousands of miles, whenever I take the cover off the camshaft to adjust
>valves, there are no depsoits and everything looks like new. I think there
>is less wear, mainly due to the ability of synthetic oil to flow well in
>very cold weather. I think things are cleaner because it has fewer
>impurities to break down. I don't ever seem to loose compression or oil
>pressure in any engines running synthetic.
I've used castrol GTX, with a 5K mile change schedule, for over 20 years in
all my cars and have never seen any deposits in the cam box either. The
aluminum surfaces have a slightly brownish tinge which I attribute to very
minor lacquering - not such a bad thing since it can prevent corrosion.
The cam lobes have always been in excellent condition with no visible wear
at well past 100K miles.
>I hear so many people claim that sparkplugs, airfilters, oil and such make
>noticeable improvements in gas mileage and horsepower. I've never seen it. I
>am just happy if the car runs like it did when it was new during the second
>100,000 miles.
I agree. I recently decided to try Mobil1 in my '99 Integra, more as an
experiment than anything else - started using it at 20K miles. I can't say
I've noticed any change in power and the mpg is still the same as it was
with Castrol GTX.
>> i have a 96 honda civic with and at 100,000 i change to synth. oil,
>> but i chose the best (royal purple). i immediately noticed a
>> difference in the pitch and gas mileage, and best of all no leaks
>> anywhere. my car runs great now.
>
Rgds, George Macdonald
Bror Jace
> you'll see that they still show as containing 1%-10% diisodecyl adipate, a
> dibasic ester. A search at Google on "diisodecyl adipate" will turn up
> quite a bit of info, basically showng that it's a plasticizer *and* a
> lubricant. Some of the synthetic lubricants for cars like Redline etc.
> which were inspired by the jet engine lubricants are supposedly principally
> ester based polymers and dibasic esters. I'm not sure what the exact
> chemical compounds are there but there is evidently some similarity in the
> chemical makeup.
I thought (from all that I read/heard that Red Line was a polyol ester
based oil. They don't mention dibasic esters at all. I assume some
additives are added to deal with things like excessive seal swelling,
but since polyol esters are already natural swellers, why would they
use an additional plasticizer? Red Line does very little advertising
so their reputation is all they have ... especially among racers. They
really don't compete directly with the mass-market stuff so I doubt
they are under pressure to compromise their formula with cheap
additives like the others.
> >I heard from someone who called Havoline and their synthetic formula
> >is also a PAO/ ester blend … same answer I got when I talked to
> >an Amsoil booster on another forum.
>
> Yeah well when I asked Castrol about Syntec about a year ago through their
> Web-based e-mail form, they replied that it was PAO - IOW they lied.
That's great! The company's reputation of being a bunch of
disingenuous creeps just gets more and more deserved. I'm surprised
you still use their dino. I know it has worked for you in the past ...
but there are plenty of good alternatives out there. >;^)
I
> thought that Amsoil was one of those which came from the ester polymer jet
> engine lube inspired route.
Your description sounds like Red Line (polyol ester). I have heard
that Amsoil originally used some revolutionary formula 10+ years ago
(some sort of ester?) but ran into some problems with ruined engines.
They originally said that it was because the owners failed to properly
prep/flush their engines. Since this formula (whatever it was) was
such a hassle, they switched to PAO (or, more likely, a PAO blend).
Another problem is that Amsoil has a bunch of over-eager jobbers, some
who play fast and loose with the truth. I've seen Amsoil sites that
were really over the top with product claims and one which ripped Red
Line and showed how this competing 'premium' oil was actually
dangerously unsuitable for use. But, despite the fact that I'm turned
off by Amsoil's multi-level-marketing and some of the obnoxious
jobbers that preach using the stuff like it was a religion, Most of
the oil testing of this stuff that I have seen has been good to very
good.
I had my Redline 10W30 sample tested ...
http://www.blackstone-labs.com/index.html ... and found that the fear
mongering on that guy's site was totally untrue. But hey, that's the
internet fer 'ya. Anyone can say just about anything … without a
shred of proof.
I've been watching the SCCA Valvoline Run-Offs at Mid Ohio racecourse
during the last couple of weeks and 2 out of 3 of those guys (and even
a greater percentage of the winners) in ALL classes used Red Line oil.
I doubt that's an accident or coincidence. From what Red Line says on
their site, their street formulas and race formulas only differ in
their additive packages. Their street formulas use more detergent,
anti-corrosives, etc ...
> >Another forum participant posted their oil analysis after using Mobil
> >1 for only 5,000 miles in a 2-year old 5.7L Chevy pickup . Their TBN
> >was only between 2.0 and 3.0, they had high lead and a few other
> >troubling trace elements. Imagine of this supposed super-premium oil
> >was used in a car that recommends extended drain intervals twice that
> >length and longer? >:^O
>
> Do you have numbers on analyses on other experiences with other lubricants
> to compare with here?
I have seen analysis on my Civic using Redline 10W30, a Cavalier using
Amsoil 0W30, a number of Maximas using Amsoil (I forget the weights)
the aforementioned Chevy Truck using Mobil 1(10W30, I think) ... and
that's all I can remember seeing. I know that all engines will wear
differently but that Chevy truck with only 20,000 miles on it was
easily the worst of the bunch. It was well past any break in point but
still very new and most miles were highway miles so I don't know what
could have happened. I suppose the engine could be a 'bad apple' but
it is easier for me to believe that Mobil's tinkering with their
formula is primarily to blame ... especially when the lab technician
made some remark that they weren't all that impressed with Mobil 1
lately. First I dismissed this ... but not anymore.
I should be able to get you links to the raw data if you're
interested.
> >Oh, and if you call "1 800 ask mobil" they will tell you that the
> >formula is still primarily PAO.
>
> Makes you wonder.:-) At least Valvoline is not being coy about the change
> to hydrocracked basestocks.
I won't use their Synpower anymore, but because they are honest, I'll
continue to use their Max-Life and dino oils. Their Max-Life, in
particular seems like a great value. According to Valvoline it's Group
III base stock oil (same as Castrol Syntec) for less than 1/2 the
price.
Have you checked out Lubrizol's site ... www.lubrizol.com ... for
info on mineral and synthetic base stocks? Looks pretty comprehensive
to me. If the dibasic ester is good stuff, then we'll have to look at
something else to blame the atrocious Mobil 1 oil analyis on ... back
to drastically reduced ZDDP?
--- Bror Jace
Stephen Bigelow
Bror Jace <bror...@hotmail.com> wrote in message
> dangerously unsuitable for use. But, despite the fact that I'm turned
> off by Amsoil's multi-level-marketing and some of the obnoxious
> jobbers that preach using the stuff like it was a religion, Most of
> the oil testing of this stuff that I have seen has been good to very
> good.
Agreed.
Although, unless you're doing your buying at the refinery, it's *all*
multi-level marketing (just hidden). How many hands does it go through
before it gets to yours?
Amsoil has a great product, both oil filters (by Hastings to their specs)
and oil. No, I'm not a dealer.
My local jobber doesn't give me any hype, just a knowing wry smile when I
pick up the filters and oil.
If he remembers me, of course.
I don't exactly see him every three thousand miles anymore...!
George Macdonald
>> If you look up the MSDS for Valvoline's Dordrecht Synpower 0W/30 or 0W/40
>> you'll see that they still show as containing 1%-10% diisodecyl adipate, a
>> dibasic ester. A search at Google on "diisodecyl adipate" will turn up
>> quite a bit of info, basically showng that it's a plasticizer *and* a
>> lubricant. Some of the synthetic lubricants for cars like Redline etc.
>> which were inspired by the jet engine lubricants are supposedly principally
>> ester based polymers and dibasic esters. I'm not sure what the exact
>> chemical compounds are there but there is evidently some similarity in the
>> chemical makeup.
>
>I thought (from all that I read/heard that Red Line was a polyol ester
>based oil. They don't mention dibasic esters at all. I assume some
>additives are added to deal with things like excessive seal swelling,
>but since polyol esters are already natural swellers, why would they
>use an additional plasticizer? Red Line does very little advertising
>so their reputation is all they have ... especially among racers. They
>really don't compete directly with the mass-market stuff so I doubt
>they are under pressure to compromise their formula with cheap
>additives like the others.
OK - you've jogged my memory there. I recall reading something about
polyol ester at Redline's site so, as you suggest, they'd likely have an
additive to moderate the swelling of seals.
>> >I heard from someone who called Havoline and their synthetic formula
>> >is also a PAO/ ester blend … same answer I got when I talked to
>> >an Amsoil booster on another forum.
>>
>> Yeah well when I asked Castrol about Syntec about a year ago through their
>> Web-based e-mail form, they replied that it was PAO - IOW they lied.
>
>That's great! The company's reputation of being a bunch of
>disingenuous creeps just gets more and more deserved. I'm surprised
>you still use their dino. I know it has worked for you in the past ...
>but there are plenty of good alternatives out there. >;^)
>
>I
>> thought that Amsoil was one of those which came from the ester polymer jet
>> engine lube inspired route.
>
>Your description sounds like Red Line (polyol ester). I have heard
>that Amsoil originally used some revolutionary formula 10+ years ago
>(some sort of ester?) but ran into some problems with ruined engines.
>They originally said that it was because the owners failed to properly
>prep/flush their engines. Since this formula (whatever it was) was
>such a hassle, they switched to PAO (or, more likely, a PAO blend).
Hmmm, I'm a bit hazy on that but it was my impression that Amsoil's blunder
was that they basically just sold a modified version of the jet engine
lubricant in the early days... with some hopefully suitable additives.
They did a lot of damage to the reputation of synthetic oil anyway.
>> >Another forum participant posted their oil analysis after using Mobil
>> >1 for only 5,000 miles in a 2-year old 5.7L Chevy pickup . Their TBN
>> >was only between 2.0 and 3.0, they had high lead and a few other
>> >troubling trace elements. Imagine of this supposed super-premium oil
>> >was used in a car that recommends extended drain intervals twice that
>> >length and longer? >:^O
>>
>> Do you have numbers on analyses on other experiences with other lubricants
>> to compare with here?
>
>I have seen analysis on my Civic using Redline 10W30, a Cavalier using
>Amsoil 0W30, a number of Maximas using Amsoil (I forget the weights)
>the aforementioned Chevy Truck using Mobil 1(10W30, I think) ... and
>that's all I can remember seeing. I know that all engines will wear
>differently but that Chevy truck with only 20,000 miles on it was
>easily the worst of the bunch. It was well past any break in point but
>still very new and most miles were highway miles so I don't know what
>could have happened. I suppose the engine could be a 'bad apple' but
>it is easier for me to believe that Mobil's tinkering with their
>formula is primarily to blame ... especially when the lab technician
>made some remark that they weren't all that impressed with Mobil 1
>lately. First I dismissed this ... but not anymore.
Any theory on where the lead is coming from - crankshaft journals?
>I should be able to get you links to the raw data if you're
>interested.
>
>> >Oh, and if you call "1 800 ask mobil" they will tell you that the
>> >formula is still primarily PAO.
>>
>> Makes you wonder.:-) At least Valvoline is not being coy about the change
>> to hydrocracked basestocks.
>
>I won't use their Synpower anymore, but because they are honest, I'll
>continue to use their Max-Life and dino oils. Their Max-Life, in
>particular seems like a great value. According to Valvoline it's Group
>III base stock oil (same as Castrol Syntec) for less than 1/2 the
>price.
I looked for that info about Max-Life being a Group III on their Web site
and couldn't turn up anything - can't find a MSDS for it either.:-(
>Have you checked out Lubrizol's site ... www.lubrizol.com ... for
>info on mineral and synthetic base stocks? Looks pretty comprehensive
>to me. If the dibasic ester is good stuff, then we'll have to look at
>something else to blame the atrocious Mobil 1 oil analyis on ... back
>to drastically reduced ZDDP?
Yep I had it in my Bookmarks but hadn't looked for a while - very detailed
info.
Bror Jace
> was that they basically just sold a modified version of the jet engine
> lubricant in the early days... with some hopefully suitable additives.
> They did a lot of damage to the reputation of synthetic oil anyway.
I'd like to get the skinny from a knowledgeable Amsoil jobber ... but
too many who's sites I see are heavy on hype and outrageous claims and
short on real technical analysis.
> Any theory on where the lead is coming from - crankshaft journals?
The lead in oil is typically coming from the main bearings, so you are
correct. Hondas tend to show a little heavier-than-average lead
levels. I think it's from their torquey, long-ish stroke motors. That
Chevy truck V8 I mentioned might just have been put together in a
haphazard way and might show lots of lead until it's well broken in.
Only a trend analysis over time would show this ...
You can see a handful of oil analysis samples/results on an Excel
spreadsheet found here:
http://forums.maxima.org/showthread.php?s=9987813b833f594c0ee86a28abf80129&threadid=85170
Some Mobil 1 used in Nissan Maximas looked fine ... even after 8,000+
miles.
Blackstone Labs has more on how to inperpret oil sample lab results on
their site:
http://www.blackstone-labs.com/index.html
--- Bror Jace