Dealer used 87 octane

[Island Dan]

Remember your peak HP and torque numbers are at the top of the graph somewhere past 4k rpm. At driving speeds at normal RPM those 87-89-93 octane Dyno graph lines are much closer.

 

AT4 Forum Fav 👍

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[Paveslave]

Yea but now you get more than 7mpg

I just traded my TRX in on my truck and you have to use premium in it as well

 

[Pirgus]

I am actually not sure about the E85... Has anyone actually tried using E85 gas with the L87 6.2L engine? The owner's manual says not to, so I am not going to try myself. But I am curious!

 

[Pingbling23]

I am actually not sure about the E85... Has anyone actually tried using E85 gas with the L87 6.2L engine? The owner's manual says not to, so I am not going to try myself. But I am curious!

If a vehicle isn’t designed for it it’s a no. The engine, entire fuel system, and the computer programming are not designed for it.

 

[Lasllc]

used Prem. first few filliups off the lot and for the duration of the break in; but , 28K miles running only mid grade, whatever it is, with no difference noticed or felt. Premium only when towing , and that is only a 5k# RV in the summer.

 

[jakrbt]

I ran 87 in my '21 for about a year. I'd heard a ticking from time to time when I was wakling up to my truck after remote starting but didn't think too much of it. One morning I got concerned and started researching, only to discover that it was a symptom of running lower octaine fuel in a high compression engine. Starting running premium after that and the ticking went away. Truck has since been traded in and I won't use anything less than 93 octane in my '24 AT4X. It was way too expensive to try to cheap out on fuel, even at nearly $4/gal here in Texas