With a 5 speed manual and a 4.0L, 4.56 would be the best for 33 inch tires, and 4.88 would be best for 35 inch tires, if you plan on going to 35's in the next 5 years, go with the 4.88 gears, even if you don't, the difference between 4.56 and 4.88 is marginal at best and you could run the 4.88...