BA haha... nothing... watch TV, and sit on PT.net

 

When I got my 05 2500HD it was on 315/75/16's (k&n + full 3" exhaust) and got 8city/11highway. After the first motor tune it went up to 12 highway. I added the KBRacing 70mm front mount and as long as I average 65-69 on the highway I can get 14-14.5mpg, anymore throttle and its right back to the 13 range. Of course all this is on 35's with a 6" lift kit. Pulling a trailer before turbo was bad, like 7-8mpg. With turbo its a good 10-10.5mpg.

 

Changing to a street tread, narrow tire will probably have the biggest effect on your fuel mileage. Then a tune and efans. Not much else you can do besides those three to significantly improve fuel mileage.

 

A guy wants to trade me his crew cab 2500 for my truck but I dont know if I can take that big of a hit in fuel, I am getting around 20 mixed driving and around 23 on the interstate. The only thing that really interest me is getting the crew cab, along with the 6.0 and a better trans. I didnt think the 2500s did that bad on gas, I figured around 13/14 in city and around 17 interstate.Damn.

 

well i am all stock still and on 285s and a leveling kit im 11.7 around town and 14/15 highway so not as bad as some

 

I'm getting 14.1 on cluster around town and on highway. I too am thinking about a tune to help out. Maybe I could get 15-16mph? My all stock with kn drop in and the stock air box mod.

 

Tires put a hit on it and everyone is running larger or more aggressive then stock it seems I get 14.5 with 285 75 16 all terrain down from 15.5 with stock 245 tires I am Going to Efans and a good tune yet and maybe headers yet. I have a cold air intake ported th and exhaust already and they helped a little on power but didn't do anything for fuel mileage over stock. Tune has been the biggest improvement I've seen for these trucks but a custom tune not mail order up to 4mpg. My goal is to top 20 mpg with my truck with the 285s but it won't be easy

 

I get 17 pure hwy.....15.5 mixed......complete **** if I run in boost

 

Running a stock with 245s 15/16mpg unloaded with trailer 13mpg. Put on 285s on, down to 12mpg unloaded 8/10 loaded. Running synthetic oil. Thinking of Airaid Air Intake Black Tube with K&N Filter. Any ideas would be helpful. Looking to get back to 15mpg. Seems if I run it over 2200rpm highway, it hits a wall and gulps the fuel.

 

Our 2500 Suburban (6.0) gets 18mpg on the freeway all day long. Also passes CA smog with flying colors. A tune can be minorly dialed so you run leaner at cruise and richer at WOT, don't expect too much though.
K&N Intake
Texas Speed 224R
Texas Speed Stainless Long Tube Headers
Spintech 8000 Muffler