Engine Oil
Daniel Pasono
From asking around I'm getting two different stories about synthetic oil.
One group says it's the best because temp doesn't destroy it and therefore
you don't ever have to change it, just its filter.
The other says, it's pricey and still needs to be changed because nobody
make a filter that good.
Oh yea, I was also told that truckers use synthetic because you don't have
to change it (which made me think of this group).
I figure if anybody know about engine oil, it's you folks.
So what do ya say? Standard oil or synthetic?
Thanks for your input.
Daniel
Comm Center
28 Nov 96
There is little difference between synthetics and conventional
hydrocarbon base oils. One is man made, the other is natural. It is
true that synthetics will take a little higher heat range but this is
due mainly to the manufacturer's additive package. Longer intervals
between oil changes is a very big NO NO unless you can validate such an
extension of changes through use oil analysis (spectrographic-Atomic
Absorption method). Lube oils (regardless of type) not only lubricate
but also act as a coolant AND a scavenger. In the latter role, the oil
must take the smaller particles (less than 30 micron) which the filter
cannot take out and keep them in suspension in the oil until the oil is
changed. AND, oil change-out is the ONLY way to get them out. No
conventional filter will take out solid particles of less than 30 to 40
microns UNLESS it is what is referred to as a "by-pass" filter which is
usually found only on heavy trucks, const. equip., etc. A by-pass filter
will take out impurities down to about 4 micron and will filter ALL oil
in the system ONLY once about every 4 to 5 operating hours with most of
the engine oil continuing to pass through the main filter. Main filters
cannot be designed to take out particles as small as 4 micron as
there would be so much back pressure the oil circulation would be slowed
down to the point of a lubricant starved and burned up engine. Another
danger of synthetics are those such as Mobil 1 which has a very high
powered solvent additive package in it. Putting it into an old engine
can suddenly release so much sludge that many oil passages are blocked
and the engine malfunctions and/or burns up from oil starvation. A very
little known fact is that the manufacturers of synthetics (such as Mobil)
use them very little themselves. Basically the only 2 places they do
use thier own synthetics is in a closed area where conventional oil fumes
cannot be tolerated and second in places such as remote pipeline pumping
engine stations which are accessible only by helicopter. Yet another
aspect of the two is that synthetics ALSO have to have an additive
package added to it and that add-pack, as it is called, does have a
finite life. Once the add-pack is worn out, accelerated wear rapidly
sets in and this will begin usually after about 3 to 4 k mi or 4.8 k km.
When you look at the cost of synthetics as opposed to the little benefit
gained by their use, it becomes obvious that their use is not cost
effective. Stay with a good conventional and natural hydrocarbon base
lube oil, change it and the filter each 3,000 mi (4,800 km), or more
often if operating on dusty roads or salt laden streets, and you will be
in pretty good shape. At to whether or not we know what we are talking
about, take a look at where your advice is coming from at the URL of
http://www.netside.com/~parsec/parsec.htm (Ref: 1 micron = 40 millionth
of an inch)
slick
>I figure if anybody know about engine oil, it's you folks.
>So what do ya say? Standard oil or synthetic?
Oh no, here we go again.
The most popular brand af oil used in big trucks today is Shell
Rotella. The most popular grade of Rotella is 15W40.
Shell Rotella is outselling it's nearest competitor by something like
a three to one ratio. Rotella is a NON-synthetic oil... ie:it is a
standard based detergent oil.
I don't think trucking has jumped on to the synthetic oil band-wagon
yet because of the higher costs associated with synthetics. Diesels
also have their own peculiar problems, one of them being oil
contamination from SOOT. This problem is bad enough that I am certain
even synthetics would need to be changed at regular intervals if they
were used in a diesel engine.
For more info, check out the Shell site on the WWW
Drive safe, be a professional
Slick
Steve Bukosky
dan...@mack.rt66.com (Daniel Pasono) wrote:
>From asking around I'm getting two different stories about synthetic oil.
Oh boy, this subject seems to attract as much flack as religion and
politics sometimes. I dabble with synthetic oil and first thing to
understand is that it all isn't the same. That for another time.
Extended drain intervals can be done if you know the oil is still fit
for service. Oil in a diesel is going to look bad very soon due to
the high carbon blowby of combustion but how oil looks is no way to
judge it's fitness for service. The only way to do this is to have an
oil analysis done such at CAT offers. To maximize oil use, you should
have a bypass filter in addition to the full flow filters. These must
be changed as recommended and of course some fresh oil will be
introduced in topping off the oil level. Do all this on a scheduled
basis and it is possible to never have to change the oil.
So you can see that effort is made towards maintaining the oil. No
body can just get by with keeping the oil level up and that's all.
With this effort of oil analysis and bypass filtration, you can
reduce you long term cost of oil and filter expense and likely add to
the time before overhaul.
Steve Bukosky
sbuk...@execpc.com Exec-PC World's Largest BBS
http://ourworld.compuserve.com/homepages/sbukosky/
Scott Valler
Unfortunately, whether you use synthetics or standard oils depends mainly on
the temperatures, compression ratios, addative package blended with the oil,
and how much money you have.
The only main advantage of synthetic oils are the increased shear coefficeint
which means the oil film holds up under higher pressure and/or torque.
The interesting thing about oil is that the addative package is what
determines the significant levels of lubrication and protection available. As
most oil manufacturers only make a small amount of revenue from lubricating
oil, and the majority from fuel, they have no monetary incentive to make oil
incredible. So, they mainly make it workable, and let it go at that, as great
oil would reduce fuel consumption and hurt their profits.
Oil life can only be properly judged by regulary oil analysis. Given regular
oil analysis and todays oils, you will only get a small increase in oil life
as the addatives wear out long before the oil is dead.
So, run standard petroleum based oils and change them regularly, with
at least quarterly oil samples to keep an eye on the wear particle levels and
acid levels, and consider using an oil supplement metal treatment that is NON
solids based.
Avoid anything with PTFE or Teflon in it as that will build up on your engine
and eventually become detremental.
Also, if you are fishing for names, most people I meet run either Shell
Rotella-T 15W40 or go with DA Oil.
Good Luck,
Scott Valler
bobw...@aol.com
I've been using Amsoil sythetic for a number of years in all my vehicals.
A couple of cars that don't get much use and a motorcyle that gets a
little more and my Volvo white with a 3406B cat which has 750,000 miles
and has not been rebilt yet and the oil consumption is about the same as
when it was new. I change oil about once a year at around 100,000 miles
and change filters every 25,000 miles and take oil sample every filter
change. So far its worked out great for me. I seen a 25 degree drop in
temp in the trans when switched it over and about a 15 degree drop in the
rears.
Bob