What Is The Best Oil?

[E-30Dubbsz]

I just got my 1991 e30 318is m42 it has 239000km on it but it runs strong. Im feeding it 91 octane and planning on getting a full tune-up in the next couple weeks. I'm also doing the oil change so i can also check for lose oil pan bolts:)

Im thinking of putting synthetic or semi-synthetic oil in for my oil change. I want to know which one is better for my motor or even if a totally different one is better please suggest it. Even the best brand would help out too. Any advice is good to me.

-Dubbsz

[asubimmer]

I always run redline for every fluid in my cars including the motor oil

[E-30Dubbsz]

is that full synthetic?

[strad]

Yes. Redline is synthetic, and it's good stuff.

I run castrol syntec personally -- I believe it burns very little if any. And I have over 300,000 kms.

[tjts1]

I don't know what the best oil is but I'm partial to Rotella 5w40 synthetic. Usually keep it in there for 7-8k miles.

[MrCleanE30]

I have been a user of AMSOIL, they were the first in Synthetics and I figure they probably have the most R&D experience as well.

[RED IS 91]

Use the search engine .

You will get as many answers as there are oils including not using synthetic because your engine will spring leaks if it's a high mileage engine.
As for me I use 15/50 mobil one.

welcome to the group and good luck with your new purchase

[E-30Dubbsz]

Use the search engine .

You will get as many answers as there are oils including not using synthetic because your engine will spring leaks if it's a high mileage engine.
As for me I use 15/50 mobil one.

welcome to the group and good luck with your new purchase

thanks, ive been waiting a long time to be a part of it ... even though my car is in bad shape body wise it runs beautifully wit 239000km on it. I think i might go for a high mileage motor oil then to be on the safe side.

[JHZR2]

Amsoil AFL European 5w-40: (http://www.amsoil.com/storefront/afl.aspx?zo=1556971)
http://www.amsoil.com/storefront/afl.aspx?zo=1556971

Good viscosity, good HTHS for out variety of engines. Top notch synthetic oil formulation.

JMH

[P. Kennedy]

+1 for Shell Rotella 5w-40

[teamgtnfx01]

dam i have 66k and use regular conventional oil such as shell but my last oil change i put in some 10w 40 castrol


am i doing something wrong

[sheepdog]

I don't know what the best oil is but I'm partial to Rotella 5w40 synthetic. Usually keep it in there for 7-8k miles.

Agreed, after seeing what has happened with oils over the years, this is the safest bet.

[JHZR2]

my only gripe against rotella is that if the engine burns oil, the HD diesel oils will destroy the catalytic converter faster than non HD oils. It has to do with the presence of zinc and phosphorous AW adds. it is the greatest bang for your buck oil out there, though, IMO.

JMH

[Jak318]

my only gripe against rotella is that if the engine burns oil, the HD diesel oils will destroy the catalytic converter faster than non HD oils. It has to do with the presence of zinc and phosphorous AW adds. it is the greatest bang for your buck oil out there, though, IMO.

JMH

I don't know for sure about destroying a Cat, but it is the oil I used in my dump trucks for over 5 years and I never had any trouble with the Rotella HD oil. Of course there is no cat to ruin on those big rigs. As for my car I run Castrol Syntec.

[tjts1]

If the engine burns enough oil to worry about the health of the cat, you have bigger problems to worry about than your next emissions test.

[JHZR2]

but remember, it is cumulative... and the "ash" (inorganic AW add packs) level in the HD oils is MUCH higher, especially these days.

Still the rotella syn is a great oil, and hopefully folks arent burning much :)

JMH

[D. Clay]

A friend of mine owns an Audi A4 and he put Castrol GTX 20W50 in it because that's what he always used. One morning it was 20 degrees in Dallas. He started the car remotely in his driveway for it to warm up. When he went to leave the engine wasn't running and it wouldn't start. It cranked like the timing belt was broken. Since it was under warranty he had it towed to the dealer. The service rep asked him what oil was in the car and he told him. They changed the oil and all was well. The thicker oil had pumped up the lifters just enough to keep the valves open. The dealer had several other cars with the same problem.
I use Castrol GTX 20W50 in my M42 whether Audi's like it or not. It freezes at least once a year here but the winter nights usually average 45 degrees.

[Shift_Now]

In the summer I've been running Royal Purple 15-40W and have had no problems so far, and I do several auto-crosses and lots of mountains road driving.