I have a 6sp w/ 4.10 gears and 33's. I'm very glad I have an 07 w/ the 4.10 gears. I would not want the 08 3.73's in my setup at all. I regularly get 16.5-17 mpg , calculated manually. I was getting 18.5-19 mpg w/ the stock 32's. I very rarely have to shift down for hills but the jeep works Hard to keep speed. I wonder if 4.56 or 4.88 would be a better match....

 

The 4.56s would probably be perfect with 33"s. 4.88s would probably put your rpms in the stratosphere I only went with 33"s because I didn't really want to regear, and hoped I'd be happy with this setup. The jury is still out on this one. My father in law is in love with the look of my jeep with the tires and lift and is waiting to see if I want to sell, so I possibly might go to 35"s and then will regear to 4.88s. I've always said if I regear I'm going bigger.

 

I'm running 33s with the 3.73 gears and its doing good. There was a lose of a little performance I'm sure but its a Jeep! I'm happy with the pickup, highway ride, and gas mileage.

I say its a definate GO FOR IT move!

 

Well I have an 07 that came with the 3.73 gears and the 6 speed and 32's now i am running 35's and rear geared after about 2 months to 4.56's and now i am getting around 16 which was about the same as with the stock set up, but i hated the 3.73's there was no power and i tow a 3000lbs boat and that was a killer. The 4.56's are great with the 35's i might have gone with 5.13's if the front wasnt a dana 30 but when i get around to swapping that out to a dana 44 i might regear to 5.13's.

 

hey MuddyToy, when & where did you get 4.56 gears from? what brand? i havent been able to find any for the HP D30 or D44 for the JK.