got a 99 f150 3:55 gears in back and not sure whats in the front. truck sits on 33's. do i need to change the gears to comp for the tires?? what kind of ratio is good for me.
i know nothing about differentials so if someone can help
thx

 

The fronts have to match the rear or you will have big problems. With 33s a 3:73 ratio would be better but are you looking for more power or what?

 

i want a little more power but im not looking to climb trees or nothinthe gears that are in my truck are stock so if im wrong on the first post than i must have read the plate wrong

 

Your front and rear gears will match, if they didn't you would know. Your 3:55's will work with 33's. If you upgraded to 3:73's you would get close to the original ratio before you got bigger tires. Of-course if you want more power and better MPG's in town then go with the lower gear.