I have a 05 fx4 and just put 33" Baja Claws on it. A friend of mine told me I should change my gearing when I told him it felt like I had lost some power. Does anyone know what gears are currently in my truck and what gears I would have to change to? I also want to lift my truck later with a 4" or 6". Will I have to regear again? Or does it only matter with tie size? Also how much would this cost me? I would appreciate any help, I have no idea!!

 

Your FX should have 3.73 gear ratio which you can get away with that running 33 tires. If your going to lift in the future I see you going to a 6in fab lift, 35" tires, gearing at 4.56 ratio, recal. the computer, upgrade breaks, front alignment, and side steps. Cost approx. $6500.00 depending how much of the work you do.
To regear go to 4.10 ratio about $600 per axle to answer your other question.If your going to regear do the rear and front.

 

I agree. And yes, you have to do the front and rear.