that's what every dealership will say - "Change your oil every xx miles". I don't believe that's entirely correct.

There are a lot of articles related to the "what's the best oil for cars" research out there on the Internet. These all say different things of course regarding the intervals and the type of oil used, however they all agree at least on one thing: when engine has too much of oil it will do a lot of damage to the engine due to foaming and not being able to lubricate it properly.

My point is that if you plan to keep your car longer,  just check the engine oil level right after the car service. There is a good chance it's too much oil. Nobody cares about your car except you - the owner.

I've seen one guy ordering his large porch to be painted. After the job was done the owner examined the paint job and asked contractors to redo everything. I saw the contractors "fixing" their paint job 3 times. And I saw after the third time the owner still finishing whatever contractors missed.

The same applies to everything: if it's not theirs - they do not care, or at least the majority. And if you want to do things right - do it by yourself. I had to remove almost 1 quart of oil from my car after it's been serviced.

If you can't change oil (it's hard for some cars), then I believe the best thing to do would be to purchase the correct oil and oil filter in Costco or Walmart store, then bring it to  mechanic you trust, and have him change it.

My car's favorite oil is Mobil1 full syntetic 5w30.