My 05 is getting aroung 12 mpg US rught now..... But its cold, things are stiff, it idles constantly, it has stock height duratracs and 3.73's. Oh and about 1500 more lbs in it constantly than a stock truck. Completely stock with no additional weight I was getting high teens at around 70 mph on the highway. I might even have a hub bearing piling up right now..... I should really check that.

My warm weather mileage ( above freezing) is usually 14 mpg or so. The Duratracs will go in the dumpster forever in the spring and I expect a gain from that too. Mods in sig....... But not one change I have made to the truck has improved its fuel economy... well maybe the e fans but so minimal you don't notice.

 

Not a 6.0. But I gained 3-4 hwy MPG with my cam/heads/full exhaust on my 5.3.

 

I get about 250 miles to a tank.

 

Congratulations, lol.

I should add I don't drive for fuel economy so I honestly don't notice. 80 mph highway or better and lots of wide open throttle don't exactly give good numbers. So..... I have noticed no gains with my truck over stock. No matter what I get 12 in the winter and 13-14 in the summer. Maybe if I drove like a grandpa I would notice a change, but I don't.

 

Mods in sig. combined average is 17 mpg. I know it will get low 20s on the hwy at 65 or so. Starts to get pretty thirsty at 70 and above. Truck with mods, stereo and sound mats tips the garbage dump scales at a little over 5200lbs.

 

That is crazy!
ive only got that one time and i was WOT alot while tuning.

 

10.5 hwy

 

Come to Houston and see how your gas mileage changes, lol. There's probably 20 stop lights on my short trip to work and none of them are coordinated

I get 16.5 mpg highway. When I towed my gf's car from AZ to TX I go 14.5 with the cruise set to 80 with a couple bursts over 100 so the mileage isn't all terrible. But stop and go it's aweful.

 

Yeah... I still don't know how I pulled that off.

 

I get same exact mpg here long as I don't get into boost too much.