5w30 synthetic in the m20?

[kman_e30]

i need to swap out my oil cooler, while im at it im going to do an oil change. i have a ton of mobil 5w30 synthetic at my house, is this going to damage anything? i dont mind spending the 20 or so bucks on the 20w50 if 5w30 is going to damage my engine, but at the same time if im not going to have any issues i dont mind saving the 20 or so bucks either.:p also i do track my car(drift) and i live in california

thanks

[MR 325]

Way too thin in my opinion. I would not and will not run anything other than 20w50.

[e30leigh]

we run 5w30 fully synthetic castrol oil in our 320i m20 race car, rules state its fully stock standard running gear. we do about 2 race meets between oil changes. everytime its clean, no signs of engine wear at all. engine isnt noisy, just the usual minor tappet tick that is present on every well adjusted and tuned m20 motor.
id go hard with the thin oil it can't hurt anything. i plan to use it on my turbo m20. either that or castrol tws motorsport oil which i think is 10w60?? whats used in all "m" engines.

[stamar]

Way too thin in my opinion. I would not and will not run anything other than 20w50.

It will burn.

did 10 30 once and it leaked out at 1 quart per 1000 miles

back to 15 50 and hardly anything burns.

I do not believe it will be a disaster as much as it will cause a dirty combustion chamber. better than dirty oil but worse than the right oil.

take it to napa or whatever they will let you exchange it no problem. no receipt, done it many times. especially if you track your car in cali...

[e30leigh]

strange? thats alot to burn. we havnt had any burn what so ever. perhaps your compression was down with worn rings? or perhaps we are changing the oil at such intervals it isnt noticed.

[dnguyen1963]

5W30 in the winter and 15W40 in the summer for me. If you drive aggressively or race your car then use 15W40 to be safe. You guys in the warmer climate are lucky such that 15W40 can be used year-round. Up here in Madison, 15W40 would not turn the engine over when the temp drops below 20F.

[7pilot]

If the front main seal, the rear main seal, and the cam seal are recent, then switch to a synthetic. The the seals have miles on them, and are hard, the synthetic is going to squirt past them under pressure.
The M20 is an old design with larger galleys and less machine tolerance internally, so oil pressure with the lighter oil may be on the low side.

m

[immajackuup]

0w40 or 10w40

[kamotors]

I wouldn't go thinner than 15w-40

[stamar]

strange? thats alot to burn. we havnt had any burn what so ever. perhaps your compression was down with worn rings? or perhaps we are changing the oil at such intervals it isnt noticed.

My rings might be worn they probably are. the leak rate goes up more than 5 times though.

My burn rate with the right oil is way below what a new m20 supposedly does.

im with ka motors I would only go 15 40, 15 50 and 20 50. Wouldnt even do 10 40 in alaska.

Particularly the op is 20 50 or 20 60 territory.

[kman_e30]

i just went ahead and bought the right oil, my dad bought like 3 case of the 5w30 because it was on sale at costco, all our other cars use 5w30 except my e30 and my dads mz4.

thanks for the help guys

[stamar]

good move.

even if you bought it at costco oreilly still has chevron 5 30 you can try to exchange next time.

You do have to lie to them but they will often be down.

Even better if its kmart or wallmart.

Ive got 4 cars all different I do it all the time to napa.

5/20
1030
10 40
20/50

[MR 325]

i just went ahead and bought the right oil, my dad bought like 3 case of the 5w30 because it was on sale at costco, all our other cars use 5w30 except my e30 and my dads mz4.

thanks for the help guys

Good man, thanks for listening.

I recommend Valvoline VR1 20w50. A little more money but it is great oil and will stand up to the abuse you put the car through. Don't go synthetic, not worth the extra cost and extra leaks. :)

[TurboJake]

5W30 in the winter and 15W40 in the summer for me. If you drive aggressively or race your car then use 15W40 to be safe. You guys in the warmer climate are lucky such that 15W40 can be used year-round. Up here in Madison, 15W40 would not turn the engine over when the temp drops below 20F.

I run Rotella 15-40 for winter oil as that's the recommended viscosity down to 20 below. VR1 20-50 for summer. Never once had an issue starting or turning over.

[navytapaul]

I run 10-30 and it seems like I should be using 20-50 now. It burns a little quicker than I want it to and being down here in Texas seems like the obvious choice.