Front suspension pop - LBJs? (1 Viewer)

[MJK]

Hi All,

I'm sorting out my new-to-me 05 LX, and after doing all the normal preventative maintenance (all fluids, filters, brakes, belts, tees) I am wondering what if anything is needed related to the front suspension. I've driven it about 500 miles on and off road since I got it sorted out, and it is generally very smooth, responsive and well behaved.

I have on a couple occasions gotten a light pop from the front drivers side when going over a small speed bump slowly. I can replicate it by doing the pry bar under the elevated wheel check (again driver side only). If I think about it hard enough, this may have been after only driving in water and sitting. I get nothing of the kind off road, and it won't do it twice. For example, it pops on speed bump #1 or pry bar test # 1, but not if repeated. I feel no play (side to side, in/out or vertically) and I see no torn boots. Oddly, small bumps seem to upset the smooth ride more than larger ones.

Based on what I have read, I would guess the most likely candidate is an LBJ just starting to show its age, but I'm hoping someone more familiar with these trucks can offer some input from the attached photos?

Truck is all stock and has 135k street miles on it. Thoughts?

 

[vman07]

Check 3 front diff bushings as well. Just did mine and I reduced clunks and thunks.

 

[JunkCrzr89]

I can replicate it by doing the pry bar under the elevated wheel check

Ball joint. Watch for vertical movement in the upper or lower joint while doing this test.

 

[2001LC]

 

[MJK]

Check 3 front diff bushings as well. Just did mine and I reduced clunks and thunks.

Will do, thanks. I had not thought to check that.

Ball joint. Watch for vertical movement in the upper or lower joint while doing this test.

Yep, understood. I don't see any (upper or lower). I suppose they could be early stage as @2001LC shows?

Thanks for the input guys. I'll check the diff bushings tomorrow. If nothing else comes to light, I am assuming a pair of 555s for both lowers is the recommended course of action?

 

[MJK]

@vman07 - you were on the money. Thanks for the pointer, I would have never suspected. The driver's side front diff bush is toast, and the front lower is bad enough I am just going to replace all three. Let's hope this fixes it, or I will be back for ball joints.

 

[vman07]

@vman07 - you were on the money. Thanks for the pointer, I would have never suspected. The driver's side front diff bush is toast, and the front lower is bad enough I am just going to replace all three. Let's hope this fixes it, or I will be back for ball joints.

The old diff cover bushing can be unpleasant to extract, and you want a ball joint press or something similar to press in the new diff bushing...

 

[MJK]

The old diff cover bushing can be unpleasant to extract, and you want a ball joint press or something similar to press in the new diff bushing...

I have an air hammer and a basic OTC ball joint press. Hopefully between those and some creativity I can make it work.

 

[MJK]

Oddly, small bumps seem to upset the smooth ride more than larger ones

New diff bushings are in, and this behavior is gone. Everything from the front end now seems more connected / less sloppy.

Check 3 front diff bushings as well. Just did mine and I reduced clunks and thunks.

The lower driver's bushing was shot, the front diff cover pillow was going, and the rear mount was fine. I swapped them all because I had them, but next time I will order another OEM pillow and put a SuperPro urethane bushing in the lower driver side.

If anybody finds this later, I purchased a $40 IR air chisel for the front diff pillow which was totally worth it. I didn't bother to cut out the center rubber before using the chisel, did the vice grip and hammer to straighten it out during removal, cleaned the pocket with a Dremel sanding drum, and then greased and pressed in the new one with an OTC ball joint tool. Fiddly to get it aligned, but all done thanks to info found here on the forum here and here.

 

[flintknapper]

New diff bushings are in, and this behavior is gone. Everything from the front end now seems more connected / less sloppy.


The lower driver's bushing was shot, the front diff cover pillow was going, and the rear mount was fine. I swapped them all because I had them, but next time I will order another OEM pillow and put a SuperPro urethane bushing in the lower driver side.

If anybody finds this later, I purchased a $40 IR air chisel for the front diff pillow which was totally worth it. I didn't bother to cut out the center rubber before using the chisel, did the vice grip and hammer to straighten it out during removal, cleaned the pocket with a Dremel sanding drum, and then greased and pressed in the new one with an OTC ball joint tool. Fiddly to get it aligned, but all done thanks to info found here on the forum here and here.

Does anyone happen to have the OEM part numbers for these bushings/stoppers? I am going to be into my front end doing some work soon and want to replace these as well.

 

[JunkCrzr89]

Does anyone happen to have the OEM part numbers for these bushings/stoppers? I am going to be into my front end doing some work soon and want to replace these as well.

Front diff bushing replacement?

Damn, you have to remove the entire diff to do this job? MIne's shot, too. I did this without removing the diff. Would of been easier if I did though.

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