my truck an 04 ford f150 has 235/70-17 tires
wats the biggest tires i can get to fit the stock rim because i want to lift it up but i dont want to have to buy new rims for it

How wide are the stock wheels? How much do you want to lift?

You could fit 54's on the stock wheels if you like, but its not too good of an idea. Generally with the F150's of the body style, 3-4" of lift will clear 33's, 5-6" of lift will clear 35's. Of course you can always do some trimming to fit bigger tires with smaller amounts of lift.

Shop around for tires that you like, in sizes that fit within the general guidelines I gave, and are no more that 4" wider than the width of your wheels.

well im thinking about buying this one kit that lifts up the front up 2" and the rear 1"
and the tire size is p245/75R16

With a 2" front 1" back lift kit you can easily fit 35" tires on the stock 18" rim I did that on my old 05 F150 and on my friends 04 F150.

Nosebag said:

That in itself has been the general guideline, but not necessarily reality. In offroading, a 33x12.50 and 35x12.50 work best on 8" wheels. They work really well on the street too. The 4" rule is close but 4.5" inch difference is perfectly doable. Just letting you know as maybe it opens your choices a little.

2007 F150 4x4
35" BFG AT KO's (315/70/17 on stock wheels)
Bilstien 5100's front and rear, fronts are set at 2" Preload

onac255 said:

33 12.5 need a 10 in rim or you will wear out the center

kawabunga 750 said:

He is right.