i have a 97 dakota 4x4 3.9 v6 5 speed and all i have done to it is 3 inch body lift and 33 inch tires..the truck used to get about 17 mpg before everything. but now i have these tires on it and i get about 8-10. it has 3.55 gears from the factory i dont understand why it would be so bad. do you think if i gave it a good tune up with spark plugs and wires and throttle body spacer and cold air intake that would help? when you fill it up it stays on full for a while but then after it comes off it you can almost watch it go down..but then i dont understand why if my trucks on 1/8th of a tank and i put 20 dollars of gas in it at 2.98 a gallon i get almost up to 7/8s of a tank. thanks for the help

 

Heavy tires (33's) = heavyer load, go back to your old tires if you can afford the lower gas mileage.

 

Hmmm. Raise the truck and increase frontal wind resistance. Larger tires which take more power to rotate and 4wd. Plus 33" tires are going to effect your odometer/speedometer unless you had it recalibrated.

BTW Dodge trucks arent exactly known for good mileage.