the "u" is for Unlimited...meaning the 4 door models.

 

JK= 2 door
JKU= 4 door

 

Ah I see. Then mine is a JkU

 

Unless you need to go that big, there is no need. I hang with guys that run 37's- to 40's and I have 33 A/T tires. I DO NOT play in mud but I will ride all day and make them wish they could have a JKU with the A/C cranking and loaded up with hot chicks. It is all about the travel 95% of the time. The other 5 I will give you tire size, thats why I have a winch