whats wrong with my dually?

sup guys i have a 94 chevy dually with a 454 t.b.i

but is wasting so much gas..whats wrong?

is gettting 4-7 mpg

Whens the last time you tuned it up? New oxygen sensor's? Fuel filter? Drag a hole in the gas tank? Is the air filter cleaned? Try running a k&n filter. Check into that then if you don't see a change check more major problems. Like fuel pressure regulator. sensor's etc. If the check engine light is on have that check'd. Good luck man.

definately tune up but make sure you got new fuel filter my 87 burban i have converted to dually in rear got bigger tb, headers, flowmasters tuned up with 454 fi and im getting 15 but i have a th400 with no over drive. so im happy with that. take care

4 is really low, but mine gets 6-10 with the 454 tbi depending on if it has the trailer on it (i don't drive it w/o the trailer very often). just do a tune up, but the 454 is the major problem.

4 - 7 is bad.

tune up. check the timing.

check for fuel leaks, especially the lines coming out of the tank.

sell it to me cheap... oh i dunno.

IT'S TOO HIGH, YOU SHOULD BAG IT = LESS WIND DRAG!!!!!!! JUST MY 2 CENTS!

my 89 with tbi only got 6-7 mpg, my 96 with fi gets 14 mpg. Im with the otherguys though, air filter, and tune up should help...oh yeah...keep your foot out of it