2004 L322 Rear Shock - Deep thoughts needed

Below is picture of McGregor, my 2004 L322 passenger side rear shock. (My daughters named the car). Running it home down the highway I heard some noises and noticed the RR rear end starting to get a little squirrelly. Manged to get it home and lifted up and found the shock in the below condition. These are new shocks, maybe 10k miles on them. Somehow the shock came off the stud/bushing. The bolt and everything else was still there, straight and intact. I took the nut and bolt off and inserted the bushing back in the shock. I added a large washer to the outside of the busing inside the bolt head to prevent this from happening again. (looking up internet info, I noticed BMW X5 has such a washer, but RR does not).

I am unsure how this happened, but it may be that the bolt started to loosen and allowed enough play for it to slide off.

I have it back on the road and McGregor drives without noise or handling issues. Everything fit up nice, no metal parts were distorted. The rubber bushing showed some wear (maybe due to rubbing as it found its way off. Currently it is torqued to spec and looks "right".

That said - the deep thoughts I need are should I replace the unit? Specifically is the bushing attached to the shock barrel or does it slide rather freely in (as it does now)? Looking at the inner corrosion of the barrel it does not appear that it is a "hard" press as water and road salt clearly intruded. Or, it is possible the shock assembly was/is defective. There is no side to side play when the busing is inserted into the barrel before the bolt is inserted and tightened, but it goes in and out with minimal finger pressure. Impression?

Looks like the rubber has come unstuck from its outer sleave that is press fitted in to the shock, you may be able to get new bushes if not new shock.

To my mind the bush should be bonded to the shock.

Try it with the bigger washer and see how it fairs.

Is the bigger washer as big as the shock eye or does it fall within the bush diameter?

Interesting. I did not notice the outside of the bushing was still in the shock. But the bushing part, shown in the picture, still attached, has a metal sleeve then rubber. Essentially it is three metal sleeves ( shock, outside of bushing and then inside of bushing) then the rubber which is inside the inside sleeve and then extends a bit. Not sure if this matters. I am sourcing a replacement.

Good questions. I also assumed the rubber would be bonded, but the corrosion pattern does not support this (unless the part is defective). It may be bonded to the inside metal sleeve which mates to the outside metal sleeve and maybe bonded there also for the small exposed portion. The bushing is three metal sleeves and one piece of rubber. Inside tube where the bolt passes, next layer which is shorter than rubber, then outside sleeve, which remained inside shock.

On other cars it is usually inside sleeve for bolt, rubber, outside metal that is pressed in.

The washer I added does not press against the shock, as the inside tube for the bolt and rubber bushing are longer, creating about a 1/4” offset.

I have added some markings to the picture. "A" appears, based on the discoloration, to be where the rubber part of the bushing was possibly bonded to the outside sleeve of the bushing (which is still pressed in the shock). "B" is a metal sleeve the length of the yellow line. "A1" is the exposed rubber that is inside "B" and corresponds to "A" (it has two levels of thickness - what is inside "B" and what is "A1"). "C" is the exposed metal portion of the bushing inner sleeve. Nothing prevents what happened in my instance - that is why want to add the washer. The washer I added does not press against "A1" because the metal inner sleeve - so the shock could still move the distance of "C". The washer presses against the inner sleeve and the bolt head. I am thinking I should enlarge the hole in the washer so it sits flush against "A1" and add or subtract so it is the width of "C". This will remove all movement possibilities.


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If "B" is bonded to the rubber then I'd have a go at cleaning it with a rotary wire brush or emery, along with the shock eye, and use perhaps a high strength bearing loctite to bond it back in.

In my mind, the reason "B" is only half the eye depth, is to enable the shock assembly to withstand some degree of less stressful axial deflection in relation to the mounting axis through the beyond average suspension stroke, this tallies with "C" sleeve being extended,.......I think!

I presume they are non OE?

They are not OE. Although their design is very similar to stock ones in appearance at least.

"B" is a metal sleeve - the length of the yellow line. "A1" is rubber that is thicker at "A1" (the length of the white line) but then gets thinner in diameter as it enters into "B". I would assume it is bonded in some manner inside. So rubber plus metal sleeve is the internal with C being a metal tube running the entire length of the bushing outside shell which can be seen in "A". All of these parts form the bushing that is pressed into the shock.

I have sourced a used unit for $25 and depending on the size and condition I may try and push out just the bushing and move that to the current installed shock.

I do like your idea of bonding with Loctite - it would be a metal to metal adhesion point which should work.

I just wonder if the other side's shock may also fail in a similar fashion. To avoid this I will fashion some sort of washer which will restrict it from sliding off completely. I got lucky as I was only a few miles from home, the day before I put 500 miles on the truck and a failure between points would have been a disaster.

You may well find that the used shocks that you've purchased are still in good damping order, and if they're OE then they should possess a superior bush ( )
it may actually be worth fitting them instead of faffing about, and a you say, the other side may not be far behind.

Or perhaps replace both with OE dampers.

Thanks for the advice - I was moving towards the OE direction. Now I wish I never replaced my old ones. The seller, one of the more reputable USA Rover part's source, offered up a replacement at a discount as my damper is just out of warranty. I think I will pass as the part is clearly inferior.

kg74 said:

Thanks for the advice - I was moving towards the OE direction. Now I wish I never replaced my old ones. The seller, one of the more reputable USA Rover part's source, offered up a replacement at a discount as my damper is just out of warranty. I think I will pass as the part is clearly inferior.

Click to expand...

Out of warranty, fit for purpose springs to mind, offering a discount sounds like admitting liability. Why am I telling you? You live in the land of litigation.