Mgp
 

Hey guys hows it going? new to this forum. I have a 1500HD with the 6.0. im getting 11mpg. is this normal? i would like to get 15, is that possable? if so how. the truck is all stock. i have new tires that inflated right, new spark plugs. good air filter. any thoughts? thanks.

Well that is pretty close to average. The best things you can do is Cold Air Intake, Tune, Exhaust, Synthetic Oil, and also replace the O2 sensors every 100k at least.

Yep, same here
 

I am averaging 11.9 MPG. Mostly city driving. All stock.

yea 10-12 city is avg. for a 6.0 with the 4l80 transmission.
try a blackbear custom tune.

i get about 12-13 in my vortec max, but its a half ton truck.

Mine doesn't measure Mgp. -- :D --

Mpg
 

I am about to fill my tank in the next coming days. I will calculate and average my miles then post the results when I do the following refill. 2003 Silverado 1500HD crew cab

Average MPG
 

13 is the approximate MPG for both highway and around town traffic. 2003 Silverado 1500 HD 6.0 Crewcab

With my 2001 I got 10mgp around town usually, and about 14 on the road if I kept the cruise control on. If not that would drop down to around 12.
My new '09 is getting about 16 in town and I got 21 on a trip I just returned from. But that is a regular 1500 ext cab with a 5.3L in it, not the 6L that was in my '01.