Has anyone ever done the math/comparison on the following:
Duramax - Sure, gets better MPG, but diesel is also more expensive than gas. Does the increased MPG offset the increased MPG for gas? Now..not a debate on any of the other benefits of diesel, just curious of MPG only.
6.2l - Like stated above and in the manual..higher octane = performance/better mileage. Performance aside can the mileage be verified to offset the higher price for the 91 octane? i think around here 91 vs 87 will run you 20-30 cents more a gallon.
No, I was never able to say I got better mileage while using 91+ in my 6.2
I'd say I probably got worse, because when the tune was just right, it flew and was fun to do some brisk acceleration. My fault, I know.
And yes, there was a massive difference in performance between 87 and 91. A few times I felt my older 5.3 was more responsive. The engine had a whole other feel when running the good fuel. Just better all around. I also had pinging (spark knock) on 87 as well.