I have an 06 F150 FX4 stepside with a 2.5" leveling kit. Right now I'm running 305/65/20 on it with factory wheels. I have a set of 17x9 wheels with 4 5/8" back spacing. I'm wanting to know if I can run 35's or need to stick with 33's. Any help is appreciated.

 

It looks like you should be ok running 35's.

Using aftermarket wheels you can run 35s on a 4WD if the wheels follow these guidelines:
-For an 8" wide wheel the backspacing is 5.5 inches.
-For and 8.5" wide wheel the backspacing needed is 5-6 inches.
-For an 9" wide wheel the backspacing is 4.5-5.5 inches.

 

There will be some minor trimming involved, but if you are okay with that then go for it. My 8 inch wide with 5.5 bs have no rubbing and didn't trim at all. A nine inch wide wheel with six inches of bs would be equivalent, so not sure why the fitment guide lists 4.5 to 5.5 for nine inch wide wheel.

 

I highly doubt that is going to fit very well. I had a 2.5" level with 295/65/20 which is a 35.1 x 11.6 on a 20x9 with 5.5" BS and had to trim the inner fender well on both sides. Since your tire is wider than mine and your BS is going to be almost and extra 1" more than mine you will rub the inner fender well severely. You can trim that since it is plastic but I also believe you will rub the metal on the backside also. Anything less than 5" BS with 35's is usually reserved for lifted trucks. I find it really hard to believe that that setup wont cause major problems while turning.

EDIT: No way that will fit. Too tall of a tire and too much backspace. Let me see a picture to prove me wrong. I had problems with my setup and mine was smaller than what you are running.

 

Wait, you are running a 305/65/20 which is a 35.6 x 12 tire on just a 2.5" level on stock wheels? I dont believe that unless I see a picture.

 

+1

 

Not to mention who makes a 305/65/20?? I cant find one even typing that in on google...Either you have a typo OP or something is stinky here....

 

For some odd reason, I think people like to assume all "305"s are 33's. Which is completely wrong! The Diameter depends on all 3 of the specs. 1. Sect. Width 2. Aspect ratio 3. Rim size

 

https://www.f150forum.com/f2/tire-gu...rsions-151539/

 

They are 60's not 65's. That was a typeo.