Quick Guide to Oil in Your E36

Originally Posted by jeffro3000

A common misconception. Try again.

See explanation above. It's a simplified approach.

Originally Posted by jeffro3000

Sounds like you've done a lot of research finding the "proper" OCI for synthetics. Mind if i see some of your data pointing to 6-8k? I've been doing similar research with oil analyses on samples from my M52TU to try to find the optimum interval, but have yet to come up with a conclusion.

No, I haven't done in depth person research on my own vehicles about the exact proper interval. I'm basing it off a safe interval that's generally accepted - with older engines like these, there's no reason to risk metallic particles which could be more prevalent in high mile engines causing damage because they've been in the oil for 15,000 miles. 6-8k is reasonable, safe, and not too overkill. Unfortunately I don't have time to do my own research on every last thing - if we all did that, we wouldn't have much technological progress at all.

Originally Posted by jeffro3000

Also, i'd like to point out one of your logical fallacies here: If LL-01 oils are not necessary for shorter changes, then are you saying that they are necessary for 15k changes? If so, whats the difference between using a lower quality synthetic and changing it more often, and using an LL-01 and changing it less often?

I'll return the favor - LL-spec doesn't necessarily denote a higher quality oil. It simply denotes that BMW has tested the oil and found it not to break down early. The TISB's specifically mention LL-specs being for longer OCI's, not superior lubrication properties. Just that they'll retain their lubrication properties longer. So hypothetically, you could have an oil with superior lubrication qualities that loses effectiveness at 6,000 miles, and an oil with lesser lubrication qualities that retains the original qualities till 20,000 miles; the 20,000 mile oil could end up meeting LL-spec and the 6,000 mile not. Does that mean the 20,000 mile oil is the better oil if you always change at 5,000 miles anyway? I'm not saying that's always true or always false, but it's possible.

Originally Posted by jeffro3000

Personally, i'll use a LL-01 that has been through the approval process and known to be within spec for my engine. High quality oil is high quality oil, no matter how long you leave it in. Saying that the approval is not necessary is a very ignorant statement to make. The ACEA, SAE, BMW, etc. develop standards like these for a reason.

You are welcome to use LL-01 spec oils. I didn't say having some sort of approval was unnecessary, I said BMW LL approval was unnecessary. The BMW TISB agrees with me, as does the manual. I should note that since both LL-98 and LL-01 had not been developed until the E36 was nearly phased out, it would be absurd to say that LL-spec oil is necessary for our cars. Would you not agree?

Originally Posted by jeffro3000

Sorry phantom. It sounds like you are fairly knowledgeable about E36s, but apparently oil is not your forte. I suggest you so some reading up on BITOG and gain some understanding of some of the basic characteristics of oils, and how these characteristics contribute to it being LL-01 or not (or any other standard).

Touché. I have done some BITOG reading, but I'm not an "expert" by any means. I do have a general knowledge of the subject, though.