Anything that comes out of California and the enviromental department especially, I am heading the other way. I just stick with the oil changes I feel fit the service.
Re: 3K oil changes, 'cheap insurance' and 'it's MY MONEY'
IT is your money, but it's OUR planet and if you have kids, it will be their planet one day as well.
Steve
Direct injected gas engines produce significant amounts of soot while port injected gas engines do not. Soot is abrasive so it increases wear and changing oil sooner reduces soot concentration.
Direct injected gas engines also increase fuel dilution relative to port-injected ones because some of the liquid-phase gasoline hits the cylinder walls before vaporizing.
So yes, for these engines, oil life is reduced. Relative to similar port-injected engines, shorter OCIs and/or better oils are needed if similar protection is the goal.
Here are consecutive UOAs of the engine in question i.e GM 3.6L DI:
http://www.bobistheoilguy.com/forums/ubb...rue#Post1843779
Some of the wear #s are due to 'break in' but look at the ridiculous fuel dilution in the most recent winter OCI .
Also, many of the newer GM 3.6 engines are showing chain stretch issues. I read on GMInsideNews that technicians believe that extended oil change intervals were partially to blame. The dirty oil has been causing issues with the chain tensioner and the camshafts.
Do you have the link that states:
"GMInsideNews that technicians believe that extended oil change intervals were partially to blame."
I don't see how dirty oil can cause a chain to stretch; Sounds like they're passing the buck due to poor design or poor quality parts...
+1 maybe
On forums whose cars have these GM DI engines (Enclave, Outlook, Traverse, Acadia,...) it seems, at least anecdotally, that the timing chain issue doesn't appear to extend into cars having 09 build dates and beyond, leading one to the possible conclusion that it is a parts issue.