Originally Posted By: John_K
Originally Posted By: jimsgmc
There isn't any right answer for everyone. There are LOTS of variables. What kind of oil do you use? What climate do you live in? How long are your trips? To many 3000 mile oil changes make perfect sense. If you live in a mild climate and only do highway driving going longer between changes is more feasible. It's nothing to argue about!
If there isn't any right answer, then why do they push 3,000 miles? It should be something like "here is a formula to use to compute when you should change your oil."
John
Well, GM calls it an OLM, and from everything I've seen and heard, it works pretty well.
The 3/3 continues to get pushed just to sell oil. There are few, if any, cars out there any more that actually need 3/3 (malfunctions excepted). By the reasoning that is most often offered in support of the 3/3 (you may not really need it, but your engine will be nice and clean, or alternatively my favorite: "cheap insurance") why don't you just go ahead and change your oil every week. Or every day perhaps. In virtually all cases today, the oil is performing as well at 3k or 3m as it was when it had 1/1, or less.
The fact that seems left out of these discussions is that since the time when 3/3 probably made sense (at least 30 years ago), nearly all the factors that drove that need have improved.
=====>> We've gone from carburetors that left our primitive engines' primitive oil awash in surplus primitive gasoline, to very precise fuel injection. Cars with fuel dilution are now viewed as troublesome exceptions to the norm.
=====>> We've lost the lead in our fuel, which used to leave a massive mess in an engine's oil.
=====>> Crankcase ventilation systems have advanced lightyears ahead of what we used to have, leaving our oil much cleaner and drier than it used to be.
=====>> Our engines are now programmed to warm themselves much more quickly and effectively than they did before (making short tripping less dangerous than it used to be).
=====>> Ignition systems are now much more powerful and precise, contributing to much cleaner burning than we ever had before.
=====>> And then there are filters -- much better too at cleaning than in the past.
=====>> And finally, then there's the oil itself, which is so much better now than it was before that it's amazing, and this would apply to both syns and dinos (most of which are now about as good as a syn anyway).
When you consider that virtually EVERY factor that used to weigh heavily in favor of the short 3/3 has changed hugely in our favor, it seems nearly laughable that oil companies and quick lube chains are still pushing 3/3 with a straight face.
I'm with Buster on this one.
