I've been having a mystery thud going on in the front of my 98 XJ. It was happening at lows speeds and didn't seem to matter if I was turning or not. Got underneath and saw the axle u-joints were shot along with just about everything else up front.
After new u-joints and an upgraded Crown HD steering kit, I still have the thud. The guy doing the alignment said he thought the thud was the bearings in the front diff wearing out.
Would it just be easier to just get a master install kit instead of just the pinion and diff bearings? Is there anything else I should replace since I'll have the axle shafts out like the inner seals?

Thanks!

 

i had the same thud took it to three people one which was a shop that specializes on jeep and they all said pinion bearings

my dad said it was too much hassle to fix so we just bought JY axle and swapped

 

lol, an axle swap sounds like a little more work to me.

 

Replacing pinion bearings is a whole lot more than a swap!! You need to make positively, for sure that's what it is first. It could be something as simple as your lower control arm bushings. Pinion bearings should be whining.

 

Did you take a look at your rear DS u joints?

Those ujoints thud sometimes when they are going.

 

I had no idea it was that involved. It's probably gonna be less hassle if I take it somewhere and have them take a look first.

I haven't even looked at them honestly. The sound always seemed to be coming from the front. I'll get under it tonight and look to see if there's any movement. I'd rather replace u-joints rather than rip the front diff open.

 

Sometimes the ujoints go bad and get rusty nasty inside and grind and cause vibes too. Sometimes they squeel and others they clunk.

Does it do it when you first put it into gear?

 

it's all the time. I can really tell at lower speeds though. It doesn't matter if I'm in gear, out of gear, braking, accelerating, coasting. Always there, just not as bad after doing the front u-joints.

 

I didn't get any play in the rear driveshaft, everything felt solid.