I'm getting 16 to 18 L/100km, which is something like 13 to 14 MPG. I have the Vortec 6000 LQ4 (6.0L) in a half ton truck with no mods and a heavy foot on the gas. Just a note: I've knowticed a drop of about 2 L/100km when using non-premium fuel, as well as about 2/3 the acceleration and not nearly the top end I usually get.

 

City: 12mpg

Highway: 17mpg

 

Hey cdusthockey,call it b.s., call foul, call 911. No offense, taken but it is what it is. Right now the DIC is showing 19.2 over the last 3/4 tank. I did not believe the DIC but I have checked it several times on fillup. I recently averaged 21.1 over a 140 mile trip on the interstate. Now I do accelerate very slowly, begin coasting very soon when approaching red lights or other stops, and use the "cruise" often. In other words, my "fun" factor is low. But, NO B.S. HERE.

 

sorry i thought you were saying that you are getting upwards of 20mpg city driving. i miss read those posts. I too have averaged over 21mpg on my all highway trips with my 07 NBS 5.3 4x4, but in the city i average somewhere between 14.4-16.5 depending on how i drive. I just cant believe how much the cruise can boost your mpg. ive tried to feather the pedal myself on the freeway and the cruise still gets around 2mpg more.

sorry again!

 

I forgot to add that mine is also a 2WD (with limited slip) which may help mileagesome; but I also have the 4 point whatever rear end for towing which is supposed to hurt mileage.

 

Hello all -- I drive a 98 chevy silverado z71 and I get 12 mpg pulling a 12 ' Uhaul trailer and 15-16 alone --- Hopefully my fuel mileage will go up after I installed new wires, plugs, cap, and intake gaskets. (5.7 liter)

 

I've got a 07 1500 CC 4X4 factory stockwith a little over 7k miles on itand today's check showed 14 mpg mostly highway driving. I've complained to the dealer and nothing can be done. By the way this vehicle has fuel management system.

 

I get a disappointing 15.4 AVG. combo driving. I MIGHT get 16.5, at 70mph out on the road.
07 ext cab 5.3ltr./2WD, but with Z-71 suspenders/ auto/3:42 axle/ (in)Active Fuel Mngmt./. I wish I had my 01 GMC back: 16.5 combo/19 out on the road 4.8ltr./3:23axle. Should have never gotten rid ofit.....................