Join Date: Jul 2005
Location: Watauga Tennessee.
I think you have have to look at the type of driving your doing. Smaller tires(to a point) will help MPG around town but hurt you on the highway. Either way too small or large and you could kill MPGs no matter what.
Example I have 35's on 307 gears. I get hurt around town and on the highway if I use 5th gear. But turning my 4th gear into my overdrive I get better MPG. 5th gear drops my RPM way too low and my engine has to work harder to maintain speed. If the tires were made too small I might make 1st gear useless and have to take off in 2nd gear. While in 5th gear my RPM would be too high and cost me MPGs.
95 Cherokee SE 4.0, 5-Spd, 8.25;
6.5" Rusty's Lift, Atlas II Rims, 35x12.5x15 Wild Country,Rusty's Tube Bumper, Wilderness Rack
Rock Sliders, K&N Panel Air filter, PSC steering box,
I-ROK reinforcement kit, ORO U-TURN steering kit,Conversion Headlights/Silverstars And too much $$$