im planing on doing a cammed 6.0 in the next couple months i was wondering waht kind of gas mileage i would get? i get 13.5mpg right now.

 

You must stay in the gas all of the time(nothing wrong with that of course ) My bro has an 03 SS w/3k stall, cam and longtubes and i would say that he gets between 13-15. He is not to bad on the gas while just riding around though. It could be a little lower but not by too much.

 

my 6.0 = 11.6 avg mpg

 

No joke, you must keep your foot planted in it. I've got all the mods below with my 5.3 and the extra weight of the crew cab, and I still get no less than 16.5 mpg. I got over 16 mpg even the weekend that I went out to the 1/4 mile track. If I only floor it once a day or so, I can get well over 17 or 18 mpg.

 

I think I have a header gasket leak

 

my 2500 with the 6.0 gets 11.3 all stock and i drive very conservitive

 

wow that sucks worse than mine and I have long tubes and no cats

 

If your driving habits change because of the extra power, ie you have to floor it less to accelerate, your mileage could actually increase because the engine is not working as hard. I have had the oppurtunity to drive a Ford F1-150 with their 6 cylinder and I got 16 MPG with it on the interstate. I get around 20 with mine (5.3 and 3.42's) on the interstate because this engine doesn't have to work much at all to keep pace. Make sense?

 

I wonder why its so shitty??? only has 31,XXX on her..I just picked it up 2 weeks ago..you guys have any Idea maybe as to why..BTW this is around town I havnt realy had her out on the highway..also 3:73 gears..

 

should be good on the highway with 3:73 gears
mine has 4:10 gears