I currently have 237/75/15s on my truck. I have previously had 31/10.5/15's on it without any fit issues.

I am looking to up-size, & am considering 32 or 33(10.5/15's) MT's.

Will I have any issues with stock suspension, or do I have to look at getting it lifted before I do?

What are the 15" larget tires that will fit on a stock 89 4x4 1/2 ton? Can I go to 12.5 in width?

Thanks for your time!

Copper Cohiba

 

Anything bigger than those 31x10.50s and you may have to do a little modification, like trimming the fender liner etc. 285/70-15 should work with some minor midification. Also keep in mind that you don't want to go too wide for your wheel. A 12.50 width tire is going to need probably at least an 8.5" wheel.