LMM Fuel Economy

[Sivrug2]

Craigth,
Calculating MPG is pretty simple. Never trust the on board info.

With your LMM your mods are hurting your mileage. The 6" lift and 305's are doing a 4-5 MPG hit. My experience with lift and big tires has always shown this. On my 2004.5 Duramax the pickup went from 19-21 MPG highway to 12-14 when I lifted and 305's.
I think the best mod for mileage is a Scanguage and using the "right foot mod".
The only time my mileage on the LMM is sub 10 is when pulling a 24 ft goosneck with a 18K backhoe on it. If I drive like a bat outta hell I can even get 4-5 MPH.

[More Power]

Those who shift their wants & needs more toward fuel economy should consider modifying their trucks along these lines:



Lowering the truck and adding aerodynamic improvements will help with fuel economy.

Jim

[02bymorris]

my 08 Silverado LTZ crew-short box LMM averaged 17.5 local driving. I swapped the ECM to a Kennedy custom and piced up 2 more mpg. have not tested it yet on a trip. all stock except for the ECM

[Runaway_Dmax]

my 08 Silverado LTZ crew-short box LMM averaged 17.5 local driving. I swapped the ECM to a Kennedy custom and piced up 2 more mpg. have not tested it yet on a trip. all stock except for the ECM

Even the exhaust system is still stock?

[50+]

Towing I get 10-11 and thats towing heavy, gross wt of 19k +. Local driving I get 14 -15 and the dic is usually around 15.4. On a highway run with few starts and stops and keeping the speed at 55 - 60 it will do 19+. On the same run at 65 it knocks mileage down to 17. All hand calculated. I can usually tell a regen if I watch the dic because it will go down about 2 mpg from where it normally will be. My LLY would do a little better than the LMM, but not much. I like the truck.