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Broke into the 10's!

Daubs

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Daubs Enthusiast

Daubs

Posted
Posted

I'm happy to report that my 2500HD Crew Cab 8.1/Allison is now getting better than 10 MPG city (average speed 24 MPH for the tank)! Lots of stop and go driving.

 

I pulled an all time high of 15 MPG highway a few weeks ago and just about jumped out of my seat. When I ordered this truck my Dad and a few buddies thought I was crazy. Said paying for gas was going eat my pocket book alive.

 

Now my 6.0 driving buddies are about ready to kill me...cause I'm getting extremely close to them in the city and beating them on the highway!

 

Only mods are 285' REVO's, t-bar crank, Volant intake and a Westers mild tune.

XTOAK Enthusiast

XTOAK

Posted
Posted

Where are you at on the odometer? Curious if it had anything to do with breakin....I've heard that these engines usually don't start getting their "best" mileage until you get 7000 - 9000 miles on them. And then a Westers, air kit, etc. are icing on the cake.....

Butch 02 Denali Enthusiast

Butch 02 Denali

Posted
Posted

That's some very good mileage for a big block!

 

You should see what Lyndon's newly released LLY DMax tunes are getting! I just got this back from one of the first customers!

 

"I haven't been back to the dyno yet, but I do have some very impressive results so far on the fuel economy on the 60HP LLY tune I got for my father-in-law. Since I did the tune he's averaged 27 MPG, before the tune he was around 17-18 MPG. Needless to say he's very happy. At first he was very skeptical and even checked the odometer against mile markers on the freeway to make sure Lyndon wasn't playing any games. He's still waiting to fill up again so he can manually calculate his milage. He says he's seen 30 MPG when cruising on the freeway. Yesterday, he told me he did 40 miles of driving up in the mountains, mainly in second, and was still seeing 20+ MPG."

 

I have another customer that got the 90HP tune that is seeing similar gains too, waiting for his report!

Roofer Senior Enthusiast

Roofer

Posted
Posted

I get about 17 with mine with mixed driving and I use the 90HP juice. I think with the juice on level 2 I would get a bit better.

 

The 8.1 is getting better mileage because it is just burning the oil and not as much fuel. hahahaha j/k

Daubs Enthusiast

Daubs

Posted
  • Author
Posted
I get about 17 with mine with mixed driving and I use the 90HP juice. I think with the juice on level 2 I would get a bit better.

 

The 8.1 is getting better mileage because it is just burning the oil and not as much fuel. hahahaha j/k

 

 

 

 

Ouch, that hurts...

 

Actually, my 8.1 doesn't burn much oil at all.

ebod Enthusiast

ebod

Posted
Posted

Does any one have any idea as to the what kind of Mileage the 8.1 gets when it's in a Suburban and doesn't go through the Allison? Is it better because the Allison is so heavy duty that it sucks up power? Alternatively, is the Allison better because of the extra gear?

 

Thanks

dannyukonxl Enthusiast

dannyukonxl

Posted
Posted

maybe those 33's might have something to do with it also, less engine rpms per speed with bigger tires... anywho i think a westers in my future very soon

8.1Texan Enthusiast

8.1Texan

Posted
Posted

I had 14 mpg highway on a trip from DC to pittsburgh averaging about 85 mph...i was amazed. I am so use to going ten feet at a time in crappy pittsburgh, and getting 8 mpg, that I was completely stunned by the results.

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