pinion bearing problem/idling problem

ok so i just picked up an xj and it needs a little tlc but i dont know where to start

its lifted 6 inches and when the front driveline was done i dont think it was balanced or lengthened properly because it vibrates like hell! and i think it ruined my front pinion bearing( it has tons of play and makes noise while driving, any suggestions on what i should do?

and when i first got the rig it wouldnt idle at all, so i replaced the iac and now it surges between 400-1500 rpm's,

it also has a huge crack in the exhaust mani before the o2, would that cause it to surge because its freaking out the o2?

im at a loss right now and any help would be great!!

First step - pull the front DS and drive without it till you get it balanced and figure out what's wrong with your pinion bearing and/or gears.

The crack will DEFINITELY contribute to the surging. It sucks in unburnt air and makes the ECU think it's running way too lean, so it cranks the fuel up, which makes it surge.

i already pulled the ds and the vibration went away did that this morning, but from it being unbalanced i think it killed the pinion bearing, would i be better off having mine fixed or buying a junkyard one?

i have a brand new manifold sitting in my garage i just have to find some time to do it, i hope it makes it idle smooth again

what are some of the other major problems these jeeps have?

Depends on what gears your front axle has - and if it's modified, trussed, upgraded shafts etc. Any locker installed?

If it's just a stock d30 with 3.55 gears in it, pick one up at the local pick-n-pull for $100 (get one from an early 90s to 99 axle, that way it's a high pinion one, slightly more ground clearance) and install it. If you have upgraded shafts or a lunchbox locker you could swap those over pretty easily too.

I would not be at all surprised if your gears in the existing front axle have a wacky wear pattern on them from the bearing wearing out and the pinion not being aligned properly anymore.

EDIT: also, 6" iirc is getting into the range where you need to start thinking about turning the pumpkin or inner Cs to correct your pinion U-joint angle as well as caster - not sure, I haven't ever done a lift that high so take what I say with a grain of salt.

Always give the year, engine, trans, t/case, and any other basic info/mods that might be pertinent.

Why? So people can give you informed answers.

HP non-disco D30/HP D30 CAD/LP D30, or has someone stuffed a D44 or 1T axle up there?

What have you got?

sorry guys im new to the whole jeep thing as far as i know its an autmatic stock gears on 33 1250 15 mtrs the only thing thats modified is the lift and wheels and tires and its a 4.0

slowcrawl said:

sorry guys im new to the whole jeep thing as far as i know its an autmatic stock gears on 33 1250 15 mtrs the only thing thats modified is the lift and wheels and tires and its a 4.0

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Year would help, HP D30 CAD with NP 207/231 transfer case through 91; 92+ no factory OEM HP D30 CAD; 2000-2001 LP D30.

Anyway, you will get it down! Welcome to Jeeps and to the XJ, you will either regret it or love!