mSaLL150

If you are a 4x2 I would do it. Should only be about 600 bucks and your tranny will be WAY happier in that stop and go stuff. The taller gears will keep your engine in its primary torque band more and the tranny wont be going nuts all the time.

Zax

I'm a 4x4. I didn't notice a huge difference in mpg or power but I have been reading that alot of people do it. I don't think I will for now. Thanks

jclem65

i have a 04 f150screw 4x4. would i need to re-gear both diff's ?

goracer

I have an 04 SCab 5.4l and also get 13mpg avg (8cty/18hwy) and went down from 37's to 35's. Gears will help for city only. It will increase city and lower highway but your average will improve. If you can install them yourself it's worth it. The other city mpg mod is the electric fan kit but that's almost $600 for the kit itself.

If you can do it yourself, look for someone with a FX4 selling their OEM gears. If not, get OEM for Raptor from Sunrise OE ford or other wholesale online dealer.

Black5oh

Yes

jerrybizzle

I had 33s with 3.55s and thought they were fine. A programer helps to correct tire size and shift points. When I bumped to 35s and towing the 3.55s were not enough so I regeared to 4.56. Not my daily driver, but if you feel sluggish, try a programer.