right oil for M52, 5W-30?
Lars Lange
documentation for performed oil changes and service. On these papers I
noticed that the oil which had been used was 5-30. According to BMW
themselves (the SAE chart) 5W-30 covers from -30 to 5 degree C,and the
average temperature is well above 5 C in Denmark. The oil change was
performed by an official BMW garage!
Have I missed something about the SAE chart, on my old M20 engine I was
recommended 10W-40.
Regards, Lars
John
for the 10W40.
"Lars Lange" <long...@worldonline.dk> wrote in message
news:3ee6452e$1...@news.wineasy.se...
Jeff Strickland
or 10w40.
"Lars Lange" <long...@worldonline.dk> wrote in message
news:3ee6452e$1...@news.wineasy.se...
Arne Schütte
It is not that cold in Denmark that you need 5W30 Water in your engine.
10W40 or 10W60 will do fine and will be cheaper.
Lars Lange
I will go for a 10W40 or 10W60 at the next oil change. I still wonder why
the official BMW center put on that oil in the first place. To me it seems
like they used the wrong oil for danish weather conditions!
/Lars
Jeff Strickland
you guys got pretty cold ...
You want the numbers on both sides of the "w" to be pretty close together,
or the oil is unstable and doesn't perform so well. If you need a 60 weight,
then you don't need 10, get 20. That said, 20w50 is pretty heavy and is only
used in the desert southwest of the United States and similar climates, and
then it is only used in the summer months. I think your best choice is 10w30
or 10w40 if you get temps up around 100F. A few days of 100F do not require
10w40, but if you get this sort of temp for weeks on end, then 10w40 makes
sense, otherwise you should be able to use 10w30 all year.
"Lars Lange" <long...@worldonline.dk> wrote in message
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Fred W.
"Jeff Strickland" <cr...@yahoo.com> wrote in message
news:veki302...@corp.supernews.com...
> Danish weather doesn't support the need for 5w30 during winter? I thought
> you guys got pretty cold ...
>
> You want the numbers on both sides of the "w" to be pretty close together,
> or the oil is unstable and doesn't perform so well.
That's an intersting theory... where on earth did you get that idea?
The closer the two numbers are the more the viscosity changes with
temperature. To understand this you need to realize exactly what the two
stated numbers mean. The numbers tells you what the viscosity is of the oil
is in comparison to "straight weight" oil, the first for when the oil is
cold, the second for when it is warm. No oil actually gets thicker when it
warms up. That's against the laws of physics.
So, a 10W30 oil is as thick as straight 10W oil when cold and as thin as
straight 30W oil when hot.
OTOH a 10W40 is the same viscosity as the above when cold but only thins as
much as a straight 40W would be when hot.
Surely you can appreiate that this means the former has a greater change n
viscosity than the latter.
> If you need a 60 weight,
> then you don't need 10, get 20. That said, 20w50 is pretty heavy and is
only
> used in the desert southwest of the United States and similar climates,
and
> then it is only used in the summer months. I think your best choice is
10w30
> or 10w40 if you get temps up around 100F. A few days of 100F do not
require
> 10w40, but if you get this sort of temp for weeks on end, then 10w40 makes
> sense, otherwise you should be able to use 10w30 all year.
That is not true for all cars. Many BMW engines specifically call for 20W50
oil for certain temperature ranges. The hazard of using a 20Wxx oil is that
when cold the oil will be thicker and may not pump through the engine as
readily.
Personally, I would consult the oil chart in the owners manual and go with
whatever sems most appropriate.
Jeff Strickland
"Fred W." <Fred....@myrealbox.com> wrote in message
news:bcndvv$jq4gl$1...@ID-197318.news.dfncis.de...
You and I listen to different physics instructors.
I get the whole thick-thin thing, but a 10w30 has less of a change to make
than a 10w40. If the 10/40 split was easier, then a 5/40 split would be
easier still, then we could use 5/40 oil all year long in almost every
region of the United States (let alone the rest of the world), but I can't
recall ever seeing a 5w40 oil.
When cold, you want a lower first number because this will improve the flow
rate to difficult to get to locations, but as the oil (or outside temp)
begins to climb, then you want a high second number because the thicker oil
protects better. To make the oil be both thick and thin is a trick of
chemistry that I can't explain, but the wider the range of behaviors the oil
must cnform to, the more difficult it is to keep the oil stable. Most places
in the USA can use 10w30 year around, some will want to use 10w40 in summer
for the extra protection, and some will want to use 5w30 in winter for the
extra flow abilities.
> > If you need a 60 weight,
> > then you don't need 10, get 20. That said, 20w50 is pretty heavy and is
> only
> > used in the desert southwest of the United States and similar climates,
> and
> > then it is only used in the summer months. I think your best choice is
> 10w30
> > or 10w40 if you get temps up around 100F. A few days of 100F do not
> require
> > 10w40, but if you get this sort of temp for weeks on end, then 10w40
makes
> > sense, otherwise you should be able to use 10w30 all year.
>
> That is not true for all cars. Many BMW engines specifically call for
20W50
> oil for certain temperature ranges. The hazard of using a 20Wxx oil is
that
> when cold the oil will be thicker and may not pump through the engine as
> readily.
>
I agree. There may be times where the 20wXX is a recommended oil, but not
very often. I put some in my Jeep in an attempt to slow a leak, it worked
because the oil was too thick to run out, but it was also too thick to flow
to the top of the motor upon cold starts, even in summer in the Southern
California. Leaks are better than clattering tappets, so I took it out
again.
> Personally, I would consult the oil chart in the owners manual and go with
> whatever sems most appropriate.
>
I agree completely. We can engage in some very dangerous conversations that
can go wrong very quickly. That said, why would you suppose the dealer used
5w30 in Denmark? I would have thought that would be a good winter oil in
that climate, but in summer one should change it out to a 10/30 or 10/40.
>
Fred W.
>
> You and I listen to different physics instructors.
>
> I get the whole thick-thin thing, but a 10w30 has less of a change to make
> than a 10w40. If the 10/40 split was easier, then a 5/40 split would be
> easier still, then we could use 5/40 oil all year long in almost every
> region of the United States (let alone the rest of the world), but I can't
> recall ever seeing a 5w40 oil.
I didn't say it was *easy*. It's not. In fact it is very hard to make an
oil which doesn't change viscosity with increasing temperatures. That is
why they have to add all sorts of polymer additivess and other chemical goop
to the base oil stock to make multi-viscosity oils. The wider the range,
the more additives, and themore stable the viscosity is with temperature.
>
> When cold, you want a lower first number because this will improve the
flow
> rate to difficult to get to locations, but as the oil (or outside temp)
> begins to climb, then you want a high second number because the thicker
oil
> protects better.
Well, sort of. It definitely depends on the tolerances the engine
manufacturer used for their bearings and pumps. That's why you really need
to stick with the manufacturers reccomendations.
For instance, my E34 540i (M60 engine) has a recommended temperature range
for 10W30 of only -30 to +5 Celcius (-22 to +41 Farenheit). That is not
very useable even in winter months n New England.
OTOH 15W50 gives me arange of -20 to +40C (-4 to 104F) and 20W50 gives me
arange of -10 to +50C (+14 to +122F). So what do I use? 15W50 Mobil1 od
course...
-Fred
Luis G.
Castrol), and I get it at my local AutoZone. It is supposed to work well
in the winter and the summer.
Jeff Strickland
the -30 mark to up around the +40, ą a few degrees, mark, making it good for
summer use in my part of the USA, and for summer use in the Arizona desert,
drivers should consider a 10w40 or even a 20w50. I'll have to double check
the chart that is in my head, and validate it against the one inthe book.
I use 10w40 year around because I live so close to places where I need the
extra heat protection, and the cost is about the same. I tried some 20w50 in
my Jeep motor, but it proved to be too heavy and did not flow well after
engine starts. I can't imagine anybody using 20w50 in anything but a "well
worn" motor.
Jeff Strickland
wider the viscosity spread between the low and high numbers on the bottle,
the more difficult it is to keep the oil stable. The problem is that we want
thin oil when cold, and thick oil when hot. It is easier to make an oil
provide these traits if the difference between them is narrow.
When I was a kid, we didn't have multi-viscosity oils, it was all single
grade. So, we had to put in 10 or 20 in winter and 30 or 40 in summer, but
if there was a hot winter day, the thin oil was not thick enough, and a cold
summer night made the thick oil not thin enough. All we could do was wait
until the engine reached its normal operating temp and pray that the oil
would do what it was supposed to do. .
"Luis G." <luisgm...@removemetoreplyhighstream.net> wrote in message
news:3EF08F98...@removemetoreplyhighstream.net...
Dan Buchan
> I get the whole thick-thin thing, but a 10w30 has less of a change to make
> than a 10w40. If the 10/40 split was easier, then a 5/40 split would be
> easier still, then we could use 5/40 oil all year long in almost every
> region of the United States (let alone the rest of the world), but I can't
> recall ever seeing a 5w40 oil.
You can get 5W50. Mobil synthetic, I think. I would have tried some if it
wasn't twice the price of normal 'good' oil.
> When cold, you want a lower first number because this will improve the flow
> rate to difficult to get to locations, but as the oil (or outside temp)
> begins to climb, then you want a high second number because the thicker oil
> protects better. To make the oil be both thick and thin is a trick of
> chemistry that I can't explain, but the wider the range of behaviors the oil
> must cnform to, the more difficult it is to keep the oil stable.
It isn't thick and thin at the same time. All oils get thinner as they
warm up, but a bigger gap between the numbers means the oil doesn't thin by
as much. If I remember, this is achieved by adding complex long chain
polymers that unravel with higher temperature and stop the liquid becoming
too thin. Or whatever. And yes, more of these are said to make the oil
more prone to break down under stress but I doubt this is an issue in
practice or they wouldn't use synthetics in high performance engines.
Anyway, a 10W30 might be thinner at running temperature than an 0W30
because the viscosity of the 0W30 doesn't change as much. I've never seen
the actual spec (I would be interested) but they must measure the viscosity
at some fixed low temp and again at a higher one, and each number quoted is
the 'straight' oil that has the same viscosity at that temperature.
The 10W30 and 0W30 should have the same viscosity at the higher temperature
but above that the OW30 should be thicker.
The way they number the oils is rather odd, but using 15W40 is supposed to
be like using a 15 weight oil in winter and using a 40 weight oil in
summer. Before 'multigrade' oils you might have changed your oil for a 15
at the start of winter and changed it back to 40 in summer. Which is daft
because with the engine warmed up the temperature outside doesn't matter
that much, but old cars wouldn't start with thick oil in the cold.