What grade fuel in 6.2L

[captras]

Is anybody with a 6.2L running less than 91 Oct? Initially, the 6.2L manuals stated that 91 Oct was recommended? Mine, however, states 91 Oct or higher is required and less could cause engine damage and void the warranty.

[haider320]

I would go with what the manual tells you. These trucks have adaptive timing and will adjust if there is knock detected.

 

I don't know what the manual on the 6.2 states; but I would not run anything lower than 89. If you tow or drive "with a purpose", stick with premium.

[TJay74]

I would not say the timing is completely adaptive, there are 2 main maps with timing modifiers that kick in based on knock incidents. I wouldn't run any less than 91 for sure as well.

[seamonster]

prepare yourself for lots of "if you can afford the truck you can afford the premium"

 

There are conflicting statements from GM on what it "requires" so go

with what your manual says which is premium. Premium will make it run better and

get better MPG anyway.

[captras]

I plan on using 93, just wondered if anybody has done less and noticed and difference.