nightster:
hello i have a 97 tj that i have been stock pileing parts for over a year im a solger deployed to Iraq I was going to order gears for the jeep 4:88s the tj SE with a four cyl has the dana 35 rear and the 30 frount right ? and i was alos told i would need a new carrier for the dana 30 is this true if so whear can i find the right one ?  will 4:88's work good with 35's ? I'll be home in 2 months to buld the jeep. thank you for your info

Your stock jeep will have at least 3.73s with 4 cyl so no carrier change is needed. (jeeps with taller ratios need a carrier change) You want at the very least, 4.88's, 5.13's would be better still. That little 2.5 will do a good job if you regear it properly. Actually I like the mill a lot, I have one in a 2000 cherokee and it is a torquey little motor for it size that lugs down well and with some deep axle gears it would do well off road on provide hours of fun with low gas usage vs a big 6. (weight a bit less too)  

thank you what kind of milage will the jeep get with low gears and how much do you think a header  intake and throtle body spacer will help the performance  

I was told that the dana 30 came with 3:55 gears if i dont have to buy a new carrier that is great. is their anything else i should change while im in to the diff's thanks for your help  

2.5 Jeeps with 5 speeds did not come with 3.55's. 6 cyl ones had taller gears. It should have either a 3.73 or 4.10 but nothing taller so you are above carrier break that they are talking about. As far as anything else while you are in there, it would be a good time to install a LSD in rear axle. I am against replacement locker that replace spider gears because they do not have the ability to power both wheels at differing speeds in a turn and can be a heart attack on slick roads (ice and snow) especailly in a short wheel base vehicle like that. The only locker I would install would be a selectable one  

you have been verry helpful I was thinking about an ox locker but they are spendy will the dana 30 an 35 hold up runing 35's i no the 2.5 isent a power house but it's got a bit at hight rpm's  

I would not go beyond 333's with a locker if you want to be pretty solid. Stay with a LSD. Gear based LSD's like True Trax work pretty good here.  BTW, my Cherokee has 4.10's with stock 29 inch tires and I feel it has good power for what it is and great mid range power too. It will pull 5th strongly from about 30 MPG and never needs a downshift on highway hills.