Oil for 1988 BMW M3

[e30M3]

Fisrt off great site. I have lurked around for a while and have searched for lots of info. I have a question:

I have a 1988 BMW M3 that I track heavily. I have always used Mobil 1 15w50 (red top bottle) I can no longer get this oil and was wondering what you all would recomend. I change the oil about 3 times a year since I do not base my changes on used oil analysis but on use and time at redline. The car see;s revs in the 5000-7800 rpm range for periods of 30 minute's 5 times per day over a 2-3 day period.

So I guess I am looking for a high strength oil that will not breakdown with use and heat over this time period. The oil temps are in the 210-230 range depending on the ambient temprature.

Any advice would be greatly appreciated.

Thanks,

Jordan

 

[mdv]

Wow, I wish I could get my M20 to run oil temps that low. I can see just over 260 on 90 degree days.

I'm assuming you want to stay synthetic...

I'm partial to Amsoil, so their 20W-50 should work. Redline's offerings should be great for you too. I've never been a fan of M1, though just about everyone I know with an E30 M3 runs it.

 

[windnsea00]

I would look into a 50 or 60 weight. I know Castrol Syntec 5w50 could be an option...not a full synthetic but there aren't a ton of choices in the synthetic 50/60 weight area. You could try BMW's Castrol 10w60 they use in the late model M cars. Also like mdv mentioned, Amsoil and Redline offer some quality oils.

 

[Alan]

Syntec 5w50 is choice.

 

[gtx510]

Liqui-Moly (Lubro-Moly) Synthoil Racetech GT1 10W60

$35/5L from Inter Auto Parts.


Redline says their xW50 oils are "Not recommended for street use in production engines that see sustained oil temperatures below 225°F (those engines should use Red Line 10w30 or 10W-40)."
Maybe just use it at the track during the summer??


Mobil 1 15W50 redcap was a thin 50wt that sheared down to a thick 40wt?


Do you have an oil pressure gauge?
I'd try a thickish xW40 and see if the pressure holds.
If it doesn't use (burn) oil that should work fine for winter.
fwiw, Mobil 1 0W40 is not a thick 40wt. Mobil 1 5W40 T&S would be better.

In the summer I'd look for a suitable xW50 or xW60.
Or you could try mixing xW60 and xW40, etc..
50:50 xW60 + GC should give you a thinnish 50wt?


You might also want to roam thru the additive and VOA forums and check out SLOB, VSOT, SX-up, etc.

 

[jaj]

Jordan

BMW recommends either a LL-01, LL-98, "Special Oil" or ACEA A3/B3 or A3/B4 oil for your engine. That covers a lot of different types. They don't recommend 10w-60 (they do for other engines, so it's not like they forgot...). I'd stay away from the higher viscosities - they just make the engine run hotter.

I'd be tempted to run a performance 5w-40 or 10w-40 like Redline and get a used oil analysis done after one use cycle. Terry Dyson's good for this kind of stuff - track engines are familiar ground for him.

Cheers
JJ

 

[e30M3]

I liked the idea of a 10/60 but when this engine was developed there was no 10/60 on the market. Fatory fill is 15/50.

I do want to stay with a full synthetic. I can get the amsoil and the red line locally but since I do frequent changes I was hoping to find an oil that is less money. I know it is the life blood of the engine and I will spend what ever I have to for oil, but I do want to explore my options.

Also it is good to know that Lubro Moly is finally bringing a 110/60 to the states. I agree that it may be to thick.

I have never considered a 40w as I always thought it was to thin for the extended high rpm I sustain. Am I wrong?

Thanks and keep it coming!

Best,

Jordan

 

[TooSlick]

The regular Amsoil 20w-50/ARO or even their less expensive 15w40 Marine Engine oil should work fine here. I don't think you necessarily need the 50wt in this application, as I recall BMW used to spec a 15w40 for all temps > -15C/+5F in these motors.

If the Mobil 1, 15w-50 was holding up okay, either of these oils should work just fine. The 20w-50 in particular will be more shear stable than what you were using.


TS

 

[jaj]

e30M3

You might want to read up on the AEHaas writings on thick vs thin oils. His analysis makes a lot of sense - higher flow with thinner oil, provided you have adequate pressure, reduces temperatures and improves life.

There is another "my M3 engine is eating it's bearings" post on this board (do a search), and the owner reduced his wear dramatically by switching to a lower viscosity.

I have an E39 M5 that sees about six track days a year, and I've run Castrol TWS 10w-60 (a recommended oil for that engine and readily available from any BMW dealer). I've also run a 5w-40 and I've run Castrol 0w30 (both also recommended for the S62 engine). The engine runs cooler with the thinner oil and UOA has shown no material difference in wear between any of them.

I think about viscosity this way: a thicker viscosity generates more engine heat in use, and so the engine runs hotter in order to bring the viscosity down to a tolerable level. A 10 degree Celsius difference in running temp cancels most of the viscosity difference between a 30 and a 60. At the end of the day, your viscosity choice is really a choice of running temperatures: do you want cool or hot? So long as there is adequate pressure (pump and bearings in good condition) the engine will be happy with either.

My opinion is that an Xw-40 is a good compromise. ALL the BMW recommended oils I listed in my previous post are either xw-30 or xw-40 with a smattering of xw-50's. I think you'll find the 40's are the sweet spot for BMW engines.

Cheers
JJ

 

[Stanley Rockafeller]

totally agree with jaj,
My m20 was always run on 15w50 by the previous owner. After a suggestion to change oil brands to save money (I only drive the car for 1 month per year, and I dont' wanna waste all that good money or oil), I was guided toward 5w40 Delvac.

WOW! the car revved quicker, and with a chip also got better fuel economy and there was less valve noise when cold (after the valves were adjusted correctly). Even while the car was warming up, the noise leve didn't vary the way it did with 15w50.

 

[mdv]

quote:

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Originally posted by Stanley Rockafeller:
totally agree with jaj,
My m20 was always run on 15w50 by the previous owner. After a suggestion to change oil brands to save money (I only drive the car for 1 month per year, and I dont' wanna waste all that good money or oil), I was guided toward 5w40 Delvac.

WOW! the car revved quicker, and with a chip also got better fuel economy and there was less valve noise when cold (after the valves were adjusted correctly). Even while the car was warming up, the noise leve didn't vary the way it did with 15w50.

---

I can second that!! I've run my M20 on 20W-50, 10W-40, 10w30 and 5W-40. No appreciable oil temp differences were observed (too much ambient temp. variation to be conclusive anyway) but the engine does feel much more rev happy on the 5W-40. I do hate Delvac though.

The S14 motor is pretty well known to hammer it's bearings, so I would think if he were to consider a 40wt. oil, something more on the thicker side of the scale would be in order.

 

[gtx510]

I thought 10W60 might be too thick for an older M-engine.
But mixing it 50:50 with GC sould thin it down just right.
Do you have oil pressure/temp gauges so you see if your oil is thinning with heat?

For cheap synthetics there's Mobil 1 15W50 EP and Rotella 5W40 from Walmart.

BMW's LL-98/01 oils will be thick 30wt or thinnish 40wt with a good additive package.
Mobil 1 0W40 is a bit noisy and most people prefer GC 0W30...

I also think some SLOB, SX-UP, or VSOT would be a good idea.
And some ARX

 

[Cary]

I am also a former 15w-50 user. I used this for years on my wifes 525i with a M50 engine. I switched to Mobil 1 0w-40 (BMW LL-01 approved), and contrary to what you would believe, experienced quieter startup, more power, 1 mpg better mileage, and most strangely a decrease in oil consumption from 1 quart every 750-1000 miles, to 1 quart every 2500+ miles.

 

[M3solo2]

Quote:

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e30M3
There is another "my M3 engine is eating it's bearings" post on this board (do a search), and the owner reduced his wear dramatically by switching to a lower viscosity.

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Yep, that's me. I run Redline 10W-40 in my E30 M3's S14 motor based on Terry's advice and it seems to be working great. Over 10,000 miles on my motor since my spiked Pb results and about a dozen track days. I still run the OEM oil chain tensioner and get no noise on startup with the lighter oil. Oil temps remain <220 F on the track, under 210 F prolonged highway. The added protection of Moly makes RL an easy choice for tracked cars that see higher loads.