are you guys 2wd or 4wd...hard to believe 23-25mpg in a 4x4 and with large tires??
these people who "claim" these huge mpg numbers are either relying on the over head "lie-o-meter" or don't know math!
if your running a stock 2wd with stock size tires and keepin yer speed at 60-65mph on the hiway, ya might see the 20-25mpg running empty (no load)
what gearing do you have?
auto or manual tranny?
hows the driving habits? jackrabbit starts and on the brakes hard to stop?
last time you changed out fuel filter?
the clown at renfrew suggested injectors, GCL changed 2 out... some clown eh?
GCL morons changed em out twice? did they say what was wrong with them?
what kind of mileage are you gettin on the hiway?
stop and go traffic is killer on any vehicle for mileage!!
do you load it up/haul heavy loads at all?
that bully dog thing is more then likely killing your injectors... allowing too much fuel?
are your tires aired up to maximum cold pressure?
hows the front end alignment?
Its a truck, what do expect it to get for mpg? Maybe you ought to get rid of it and buy a bicycle or walk or god forbid buy a honda!!
I saw a drop in mpg when I added leveling kit (raised front end now have more undercarriage exposed=more drag)... also saw a drop when I added bumpers(oem bumpers added to aerodynamics) saw yet another drop in mileage when I installed 35" tires...
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05 3500 QC 4x4