just got my burb fuel question

I just got my 96 lt 2500 2wd 7.4l vortec suburban. When i got it was kicking two codes random misfire and o2 passenger side before cat. Got the misfire fixed with a new cap and rotor and a new o2 got rid of the code and made it run good. My question is i put in 60 bucks in my tank at 2.65 and i figured it to be 18 gallons of gas. With that 18 gallons i was able to drive 150 miles before needing to get more gas. I figured it out to be 7 miles to the gallon. I was wondering what everybody else is getting and what i can do to help the gas mileage out on this thing.

The body man in my shop has the same set up mixed driving gets 11. Lots of issues affect mileage, the list is long, tire pressure, weight, gearing, temperatures, driving style, engine tune and conditon.

My question is i put in 60 bucks in my tank at 2.65 and i figured it to be 18 gallons of gas.

Wow: My calculator says that $60 divided by $2.65 = 22.64 gals. The only true way is to fill the tank and drive a while and fill it again. My 98 K2500 7.4 with stock tires and 3.73's and 125k gets 13-14 mpg steadliy and always has...........Steve

My question is i put in 60 bucks in my tank at 2.65 and i figured it to be 18 gallons of gas.

Wow: My calculator says that $60 divided by $2.65 = 22.64 gals. The only true way is to fill the tank and drive a while and fill it again. My 98 K2500 7.4 with stock tires and 3.73's and 125k gets 13-14 mpg steadliy and always has...........Steve You serious? A big boy in a sub and your sportin 13-14.Holy crap.You have a good one.Had to edit,just relized i jacked the thread,sorry.Triple 7 is right,you need to fill up and run then do a milage check.