Poor peformance after synthetic oil change-over

[GIXXER]

Don't think I'd use 0W30 unless you're in the extreme northern part on the country like Int'l Falls, MN and then only in the winter.

Actually, a true synthetic is good for year round use. Even in warmer summer months the engine benefits by cooler operating temperatures and enhanced ability to suspend engine soot and grime.

But yes, a 0W__ provides even greater benefits for those with cooler winters.

 

[73shark]

I suspect GM calls for 5W30 for a reason tho.

 

[Black Dog]

Yeah 0W30 is much too thin for normal temps. Why go to that from 5, to save a negligible amount of fuel? They already took care of that gain largely by going to 5W30. Going to 0W30 is just not enough reward to justify the risk.