I run the 37x14 bias ply. I have been extremely happy with them. I run 10oz of air soft BB's in each. They get flat spots for the first few miles, then smooth out and ride with no vibrations up through highway speeds. The 36 and 37 both measure about 36.5. The 36 has a more rounded balloon profile, while the 37 is slightly more squared. Off road I run them at 6 psi with double beadlocks and they are amazing. I put about 1500-2000 miles a year only jeep and am very happy with them.