Im 18 and my xj is lifted.
i want bigger tires like 37 or 38s.
but i have factory gears so should i gear it or get tires first.
and when i get gears im goin to get the 4.88 d30 front with air locker.
4.88 d44 with a new carrier and air locker also
i get a discount on tires from work

 

I would do the gearing first cause it will help no matter what.

 

Gear it. dont think twice about it.. Gear it.. slap a locker in it.. then tires!
38.5" tires: IROK!
37" tires: you know the line sucks but they dont care...
35" tires will get you anywhere...
33" tires make you pick lines better
32" tires make you wish you bought 33" tires
31" tires makes your jeep look non stock..

Mark

 

Hmmm go ahead and slap the tires on! that way you can break your axles before spending all that money on stock axles. seriously 37-38in tires do not belong on stock axles. Even the Dana 44 will be put to it limits.

But if you are insisting then make sure you have spare axle shafts and change your diff oil often becuase it won't be long before it has metal shavings in it.

 

Those big of tires you are really lookin at some serious upgrades to keep from breaking the rest of the drive train....... just my point of view
Oh and 30 years of breakin stock drivetrains with big tires

 

Im runnin my 37's on 4.10's and its not too bad. Ive lost 4th gear going up hills but I manage. With factory gears tho, i'd say its gonna be a slug. Either way youre gonna have to regear it so you might as well go ahead and do it. Also look into axle swaps cause those 37's will make a D30 go boom.


Heres how mine sits on 37's...just some motivation to start yours

 

A d30 on 35's is pushing it. 37's or 38's are asking for it to die. Don't regear it if you plan on running those size tires. You have to think about how small that axle is. It's strong for it's size but with that size tire you run the risk of twisting a tube, bending the housing, or even just having the ball joints run out really quick. I'd throw the 37's on with the stock gearing and run it till the axles brake while your building a set of D60's.

 

I concur. With 37s or 38s you might as well just buy the tires and start saving for bigger axles because gearing and locking your stockers with plans of running 37+ tires is a huge waste of your time and money. Hopefully you have an Auto tranny with an aux. cooler so it will somewhat live through your gearing and tire mismatch. With a manual, you'll be buying a new clutch about every 3 months. Hopefully, for you, your axles will live through the tire and gear mismatch long enough for you to save some money up......But, I doubt it. OEM XJ axles with 3.55 gears will die violently with 37 inch tires....just a ticking time bomb.

 

holy fawk slow down dude.

youre stepping into one ton axle territory real quick.

 

Gears and Upgrades first ...Tj (also broke stuff for over 30 years)

 

37's on stock gears....good luck, dont pull out in front of anyone. regear first then tires then replace what break.

 

If he replaces what breaks then he would have just wasted a bunch of money on fixing up axles that he's going to have to just throw away, probably becuase of a bent housing.

Reilisticly just buy you some 35's and put them on the stock axles. Then build your new axles to hold 37's or 38's. Then sell the 35's and upgrade to 37's or 38's. Should work out much better for you.

 

X2

again lol

 

i meant replace it with better parts like strange or alloy axles things like that...not just JY axles.

 

I don't care if you throw 30 spline alloy shafts in a D30. Your problem will then become ring and pinion strength. You'll have to build a big truss to keep from bending a housing and other crap. You would have droped more money into that D30 than you would have in just buying a D60 and not having to worry about breakage.