33x12.50R__ <--Fill in the blank.
I don't know what mt locks are so I will ignore. If you have OEM 17" wheels, you need a wheel spacer to throw a wider tire on. If you are ordering wheels, get the proper backspacing and you can definitely step down to a 15 or 16, only some 15's will work though. 33's will fit with no lift.
Authorized dealer: Ripp Mods, ACE Engineering, Expedition One, Rotopax, All Pro Off-road
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