Largest tire on 20s

[DKR]

Howdy all....

I have factory 275/65 20s Goodyear (came w/ my KR)

I have been told that BFG AT 285/65 20s will fit by a tire shop.

Now they make a 305/55 20. Both are load range E.

305s are of course wider, and about a .5 inch shorter.

But they don't recommend 305s on an 8" rim (which I believe mine are, haven't really checked, only have had truck couple of weeks.)

Any advice, preferences, etc???

Thanx in advance....

[shu873]

unfortunately I can't advise you on the tire option, but I'm sure somebody with some knowledge on the subject will be along soon. Just wanted to say welcome to powerstroke.org!!! Sounds like a beautiful truck you've got there.

[DKR]

Much appreciated...I have owned 9 other Ford trucks, and this is prolly my favorite.

to the site KDR. You'll be glad you found this place. That truck should prolly be your favorite, it sounds like a fantastic rig... now get us some pics of that badboy!!!

Rob

[DKR]

I know I really need to get pics. Hopefully maybe this weekend if the weather holds long enough.

[klpaul]

A 305 is only 4 inches wider than your wheel. The optimal tire to wheel combo is two to four inches wider than the wheel. This puts you on the upper limit of ideal. I do this everday for a living and you will not have a problem with the width on the wheel. Make sure you do have clearance with your upper control arm with steering but I can't imagine this being a problem. Frankly my biggest concern would be the 9/10 of an inch reduction in tire diameter. This changes your effective axle ratio by over three percent and defeats the purpose of going larger. Consider a 305/60/20 which about 1/2 inch larger diameter (only Goodyear makes right now) or the 285 which is about 1/2 inch bigger and a little wider.

I couldn't see if yours was 4x4 but if so I would think a 35x12.50x20 is OK and I would bet it would be fine on the 4x2 but I would want measure to make sure.

Sorry, I am not sure all this info really helps.

[DKR]

Originally Posted by klpaul

A 305 is only 4 inches wider than your wheel. The optimal tire to wheel combo is two to four inches wider than the wheel. This puts you on the upper limit of ideal. I do this everday for a living and you will not have a problem with the width on the wheel. Make sure you do have clearance with your upper control arm with steering but I can't imagine this being a problem. Frankly my biggest concern would be the 9/10 of an inch reduction in tire diameter. This changes your effective axle ratio by over three percent and defeats the purpose of going larger. Consider a 305/60/20 which about 1/2 inch larger diameter (only Goodyear makes right now) or the 285 which is about 1/2 inch bigger and a little wider.

I couldn't see if yours was 4x4 but if so I would think a 35x12.50x20 is OK and I would bet it would be fine on the 4x2 but I would want measure to make sure.

Sorry, I am not sure all this info really helps.

Hey, lots of good info....much appreciated...I really want the BFG ATs, so I probably are going to go with the 285/65 20s....thanx for the info.

[99Smokin73Stroker]

I have 305/55/20's mounted on 20x9 rims on my dodge, which is close to what you are thinking about. Check out my garage for pictures to help...

[klpaul]

Sounds like a sweet ride. I think you are making the right choice but so you know the BGF AT does come in a 305 55 20 as well as a 325 60 20 (I think would require a lift even with the 4x4) as well. Good luck and make sure when you get those tires make the shop cross rotate them every time to eliminate tire cupping which is a common problem with the heavier trucks and AT tires.

[akduece50]

i've seen 37's on 20's with a levelin' kit, maybe i helped