LovetheTide

This is for 2004-2008.

On a stock truck without leveling kit you can run 33X12.5" tires if it is a 4WD and 31X12.5" tires if it is a 2WD, using stock wheels.

On a leveled truck(2" kit and larger) you can run 35X12.5" tires on a 4WD and 33X12.5" tires on a 2WD truck, using the stock wheels.

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.

If the wheel specs are not listed about you will more than likely have to run 33s or even smaller to avoid too much rubber and trimming. These specs are the basics for tires fitting well but you could run 35s if the specs are very similar but you will face bad rubbing.

For a 2WD truck and after market wheels you can run 33s with wheels that fit withen these specs.
-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.

If the wheel specs are not listed about you will more than likely have to run 31s or even smaller to avoid too much rubber and trimming. These specs are the basics for tires fitting well but you could run 33s if the specs are very similar but you will face bad rubbing.

Remember that these are the basics to running aftermarket wheels and tires, certain tires might not rub but others might because of aggresive sidewalls.

These specs should work for most people and instances but if you are worried about fitment get the tire shop to mount the tire on the wheel and put it on the truck then turn the wheel to full lock in both directions to see and possible problems. If the tires you plan on running aren't 12.5 inches wide you still might be able to run 35s because of that reason, for a 4WD and some aftermarket wheels or 33s for a 2WD. It's best if you can find wheels that are a happy medium between the two backspaces for the 8.5" and 9" wheels because you will face more rubbing if you go for 6" of backspacing on a 8.5" wheel instead of 5.5 inches that's right in the middle.

For those who are curious. The stock wheels(17 and 18") are 7.5 inches wide with 5.5 inches of backspacing. The bolt pattern is 6X135mm.

Big thanks to PawPaw on this one.

If you have any instances where you find that these specs haven't worked for you please let me know and I'll make the appropriate changes, please PM so I will see it.

Hope this helps.

AusFx4

So if i have an 18x9 aftermarket wheel with 5" backspace what does that mean for me. Keep looking?

LovetheTide

That tire is really wide, very very close to 13 inches and tall. The combo of it being that wide and the backspacing of the wheels would cause rubbing, bad.

Step down to the 60 series and you'll be ok.

AusFx4

any idea on the amount of trimming id need to do?

LovetheTide

Ehh I'm not too sure but it would be a good amount on the valance, inner wheel well, and you'd probly rub the UCA forever because there's nothing you can do to fix that.

SethP

i want to run a 18x8.5 XD addict wheel with a 35x12.50. your post says that you can run the aftermarket wheels that are "-For and 8.5" wide wheel the backspacing needed is 5 inches." but then it says The stock wheels( 18") are 7.5 inches wide with 5.5 inches of backspacing." do i need more backspacing or will i be fine?

LovetheTide

I too noticed that and the info I posted is what I have seen people run on various forums and what worked for them. I didn't notice anyone using more backspacing but I believe that more would work, to an extent atleast. If you ran 5 inches of backspacing with an 8.5" wide wheel it will work but I'm thinking if you ran more, say up to 5.6 or possibly more you will be ok.

SethP

thanks cause im doing 6inches of lift but i want the tires on it first. i have the leveling kit here at the house but i havent put it on yet, figure y do it if i was going to do the suspension lift. but with this info i might as well so i can slam on the 35s

ford4wd08

all we need now is a sticky for people to start using the SEARCH function before posting lol

LovetheTide

Check with the specs on the lift because most kits require you have certain backspacing on the wheels so they will work correctly. I'd hate to see you buy a set of wheels and then lift it to find out they won't work with the lift.

Isn't that the truth.