What type gas do you use? 87? 89? 92?

[goblue4016]

Hey All,

 

Just curious what type gas so you all use for these trucks? I'm running 89 but I didn't know if these trucks perform better with one type over the other, any added performance or mpg boost with one?

 

I want to see if I'm wasting the little extra I pay for 89 if 87 is the same thing.

[nadrojcote]

Pretty sure you will not see any mpg increase using higher octane, but the engine is most likely rated for high HP with 91.

EDIT - This guy had good results with 93

 

http://www.gm-trucks.com/forums/topic/156449-christmas-road-trip-results-87-octane-vs-93/

Edited March 23, 2015 by projectsummit

[LongrangeLauber]

I've ran both 87 and 93. Small increase in performance with 93 but my mpg dropped overall by a marginal amount. I just keep running 87 and I get better fuel mileage. Not worth the extra coin unless it's required such as for the 6.2 or if you have a tuner set for a hot tune aka 91 or 93 tune

[PMattras]

I am using 87 as to what is noted in the truck manual. Why waste money if you don't need it.

[POS VETT]

E85 most of the time. So far, 93 has been used only for a few tanks and will only be used sparingly. I will not use any octane-level lower than 93.

[goblue4016]

Thanks guys... Yea I have the 5.3 so I'll stick to 87 until I get a tune eventually

[MudMutt]

I have been using 89 since day one ... Truck runs great on it ... I don't see a need for 92-93.

[nadrojcote]

what is e85 equivalent to octane wise?

[Ridersfan]

I use regular 87 for daily driving and I use premium 91 for towing my 6000lbs camper... sometimes the boat too at 3500lbs, but not always... depends on how full tank already was... but only premium 91 in the boat or else it pings.

[dbannerz71]

Saw someone post on here about the advice he was given by blackbear where he was told to run 89 octane. I don't know if it had anything to do with the tune or not, or if it was related to being just the right amount of to keep the engine from retarding the timing due to engine knock being sensed. I curious about this. Hopefully he will chime in.

[galliher_nc]

I run premium in the HC, regular in the Sierra and diesel in the 2500.

[ccdies]

87 here, Id love to run E85, but the nearest gas station is over 15 miles away that carrys it

[wurgs]

I only use 91. That's the highest anyone here carries.

[POS VETT]

what is e85 equivalent to octane wise?

It varies depending on alcohol content, but usually over 100.

[Test Alpha]

My truck really likes 89, seems to give it a little more "pep"