I need new tires for my truck(goin with BF AT's) i just want to know the biggest i can go with out any problems. I have factory stock chrome 18's. I don't have a leveling kit yet. I want to get one just need the tires first.

 

You can get 33's on your stock wheels without a leveling kit, and 35's on your stock wheels with one.

 

If you want BFG's go with the 305/65-18 (34x12.50). I'd get the leveling kit first.

 

That's assuming you are 4wd. If not, stick with 285/65/18's.

 

Get the AS kit and go with these. That is my next purchase also.

 

Yea i got 4wd, how much are the leveling kits? And any idea how much differance it makes in mpg? Doesnt really matter around town, its just i take trips to ohio and i gotta try to convince my wife lol.

 

The Autospring kit is around $80. The affect on your milage is gonna depend on the powertrain your truck has and your OEM tire size.

 

i have the 5.4l, stock tires are 275/75/18 and i dont know my rear gear, wish i did though.

 

you either have 3.55LS or the 3.73.... gas mileage wont be that bad and I mean its a truck not a car so mpg's arent going to be good to begin with....... i get like 14.5 driving round town with 35's and a 3.55LS..... highway is like 16-17....

 

I think you mean 275/65/18

 

Yea that's what i meant. Is there anyway i can tell which rear gear i have? Can i decode the vin or something? I was also just curious how wide my stock rims were. For the 305/65's it says i need atleast 8.5 inch width and i though i read somewhere they were only 7.5. But i might be wrong.

 

Open your drivers side door and you will see the sticker that is on the rear door and there should be a code number where it states axle, I know there is a website where you can check what the number represents, google it thats what i did and found mine out. as far as your stock wheel, I believe all factory wheels for these trucks are 7.5" wide, someone correct me if your wrong

 

F-150:

19 – 3.55 Non-LS
18 – 3.08 Non-LS
H9 – 3.55 LS
B6 – 3.73 LS


this should help you out.......

 

ok so i have the 3.73 LS.

 

Since you have the combo of the largest engine, lowest gears and tallest oem tires, you will have less of an impact on performance and gas milage than someone with another combo.