The Texan wrote:
My owners manual and the 2012 manual BOTH say premium is "recommended" but regular may be used. Then it goes into the fact that at altitudes above a certain point, mid grade fuel is recommended and again, regular may be used. The fact that I live at 5K' and 91 octane is NOT sold and I use NON-ethanol fuel, I guess I am going to grenade my engine .... NOT.
The OP is looking at a DI 6.2 engine not a 3 year old truck like yours. I posted relevant info to the engine we're discussing not yours, nobody cares what octane your engine runs.
The fact is GM's new line of high compression DI engines require high octane in certain models, perhaps if you read the link I posted I wouldn't have to repeat myself.
