Hey guys,

i am ready to install a leveling kit on my 05 fx4 supercrew and i dont know what to do. i need help with tires. i want to fill the gap but i dont want to rub. i was told 33's would be ok, but 35 would be better. i have a rancho quicklift 2.5" in mind. 33x12x17 on a 17x10. but like i said, i have conflicting comments coming left and right.....i dont know what to do. any ideas and comments would be great.

thanks

omar

 

As a general rule, with a leveling kit on the new 4x4's, you can fit a 35x12.50 using the OEM wheels or 33's with aftermarket wheels. Also, there have been a few fitment issues with some aftermarket 17 inch wheels on the late production 2005 and newer trucks due to a change in brake calipers. I'd suggest going with an 18 inch wheel. I think the best looking combo on a leveled 4x4 is an 18x9 inch wheel with 5 to 6 inches of backspacing and a 325/60-18 (33x13.00) tire.

 

What does backspacing mean???

 

so when measuring in inches what is the 12.50? That cant be the width of the tire is it?? What would that be in millimeters?

 

Completely agree !!

Backspacing is the distance from the wheel hub to the edge of the wheel on the inside. Contact the wheel manufactures to find out backspacing. But if it were me, I'd just stick with the general rule of thumb. 33x12.50s for aftermarket wheels and 35x12.50s for OEM wheels.

The tire sizes go by this ... The first number is the height of tire in inches. The second number is the tire width. The last number is always your wheel size. Metric tire sizes are a little bit different. A good tire chart can be found here ...

http://www.discounttire.com/dtcs/infoTireMath.dos

 

That pretty much covers it.

 

i appreciate your help....i didnt know there was a rule of thumb for these wheels....although, it did cross my mind at one point that stock rims would fit a bigger tire just because of the width...and aftermarket rims could only fit a smaller tire, again, because of the width.

again

thanks for your help

 

Why is that? Why can you put 35s on the OEM wheels, but can only go with 33s on aftermarket. Seems like it would be the other way around????

 

Becuase most aftermarket wheels dont keep the factory wheel's backspacing, causing the tire to rub.

 

good answer ! yes, most factory wheels come in between 8 and 9 inch width with very few inches of backspacing. most aftermarket wheels if you go with a wider than stock wheel, you're going to have most of the width to the inside (aka backspace).

 

As well as the OEM wheels have much more backspacing compared to most aftermarket wheels.

 

Right. If you have too much backspacing it can cause the tires to rub the contol arms and sway bars. If you have too little backspacing it will cause the tires to rub the fenders and front bumper.