I never knew it before but there are a few 37in tires that are actually in the low 36 range. Most tires are only .2in below 37in but I found a couple of tires that I am interested in that are a little bit smaller than that. The two tires that I am looking at are the Goodyear Wrangler MT/R's and the BF goodrich AT/KO's. The MT/R's are only 36.5 and the AT/KO's are 36.3's. I was wondering if I would be able to clear these with 5in or lift or possibly even with 4.5in and some trimming. I am going to mount them on 17x10 tires because both are about 13in wide. Would I be able to clear these?

 

I know for a fact that you need 5.5" to clear a 36x12.5 and a true 6" to clear 37x12.5 on a torsion bar (02-05) 1500 4x4 with no trimming. Keep in mind that almost all 6" Suspension kits for our trucks are really about 5.5" with the Skyjacker being the only exception that gives you a true 6".
With that in mind, I'd say you would probably need 6" of lift to clear a tire that is 36+ inches and a little wider than 12.5" without any trimming...

 

I got BF goodrich Mud terrain 35/12.50/17 on my 06 megacab 4x4 with only 2 inch leveling kit on front.