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View Full Version : Anyone had this rear suspension component fail?



POD
14th March 2025, 11:04 AM
A gap at the rear suspension 'trailing arm to chassis' bush caught my eye the other day and I assumed it was yet another worn-out bush but closer inspection revealed a different problem. The rear suspension trailing arm pushes forward against the bush via a large, thick washer. The washer was distorted, visible in this pic
192773
but when I looked closer, especially after removing the washer, it was apparent that the shoulder of the trailing arm was making a pretty good effort at pushing it's way right through the washer
192774

Seems to me that if this progressed to the point that the shoulder of the trailing arm pushed it's way through the washer, the axle would suddenly move forward, resulting in all manner of unpleasantness.

I've had too many of these vehicles over the years so there are always spares of whatever floating around the shed somewhere and I located another set of these washers with similar wear that I had not picked up at the time, probably because the disc had remained relatively flat and I didn't look closely at it. The washers (or discs) are of two types; the one that sits on the pushing side of the bush has a chamfer in the hole that sits over a radius on the arm. The one on the other side of the bush does not have this chamfer. I solved my immediate problem by taking a non-chamfered washer and chamfering it with a large 60 degree countersink using a drill press, working incrementally until the chamfer was deep enough for the flat part of the disc to contact the flat part of the shoulder on the trailing arm. I've flattened the other two discs and will henceforth carry them as spares in case one looks near to failing when out and about.

I'm wondering if anyone has experienced a failure where the trailing arm has punched forward through the disc and then through the bush?

V8Ian
14th March 2025, 04:09 PM
Never seen it myself, but I've never looked for it.
It might be worth asking the same question in the D1, D2 and RRC sections, they all share the same basic suspension.

Blknight.aus
14th March 2025, 08:24 PM
yes, it happens if the rubbers are not replaced when needed or the chassis bolt isnt pulled down tight enough. As the axle shunts the radius rod back and forth it turns into a slide hammer.

If the shoulder on the rod is rounded get a new rod or its just going to happen again.

also, you might want to check the threads on that one.

it looks like it might have some thread damage but that could just be the pic.

POD
14th March 2025, 09:04 PM
yes, it happens if the rubbers are not replaced when needed or the chassis bolt isnt pulled down tight enough. As the axle shunts the radius rod back and forth it turns into a slide hammer.

If the shoulder on the rod is rounded get a new rod or its just going to happen again.

also, you might want to check the threads on that one.

it looks like it might have some thread damage but that could just be the pic.

So you have seen these punch through the disc and through the bush? I've never heard of it happening but there definitely appears to be potential there. Would no doubt result in all sorts of damage- I'm picturing bent shockers, damaged tailshaft, broken brake lines etc.

I'm not sure I agree about it being from impact, I rather suspect it's from the effect of what is a tiny surface contact area pushing a heavy vehicle (my 130 would frequently be over 3 tonne) up some very steep terrain whilst articulating the radius arm; fretting corrosion probably a factor, mainly just just plain old heavy wear. Something I will certainly be keeping a close eye on in future.
The thread on the arm is ok but yes there is also some wear to the shoulder of the arm where the disc seats. it would be nice if that friction-welded threaded part had a much larger head to provide some more surface area.

Blknight.aus
14th March 2025, 10:14 PM
So you have seen these punch through the disc and through the bush? I've never heard of it happening but there definitely appears to be potential there. Would no doubt result in all sorts of damage- I'm picturing bent shockers, damaged tailshaft, broken brake lines etc.

I'm not sure I agree about it being from impact, I rather suspect it's from the effect of what is a tiny surface contact area pushing a heavy vehicle (my 130 would frequently be over 3 tonne) up some very steep terrain whilst articulating the radius arm; fretting corrosion probably a factor, mainly just just plain old heavy wear. Something I will certainly be keeping a close eye on in future.
The thread on the arm is ok but yes there is also some wear to the shoulder of the arm where the disc seats. it would be nice if that friction-welded threaded part had a much larger head to provide some more surface area.

The one I've seen the after effects of personally, was punched into an after market long range fuel tank on the driver side.

AK83
15th March 2025, 07:53 AM
I've seen bent washer myself on some wrecks, but just assumed it was due to rough handling of the hulk.

D1 and RRC has same trailing arm, D2 is different, never seen it on mine.

p38arover
15th March 2025, 11:37 AM
Never seen it myself, but I've never looked for it.
It might be worth asking the same question in the D1, D2 and RRC sections, they all share the same basic suspension.

No, we don't ask the same question across multiple fora. If anywhere, it should be in Technical Chatter.

Tins
15th March 2025, 11:47 AM
No, we don't ask the same question across multiple fora. If anywhere, it should be in Technical Chatter.

That's a pity, because unless people make regular use of the "New Posts" button the audience is greatly diminished and therefore answers are fewer.

POD
15th March 2025, 12:19 PM
A more likely problem with a heavy 130 anyway I think.

p38arover
15th March 2025, 12:23 PM
That's a pity, because unless people make regular use of the "New Posts" button the audience is greatly diminished and therefore answers are fewer.

It’s always been that way on the forum. I can’t help it if people only look at one section of the forum (and some do), e.g., some only look at the section that refers to their vehicle model.

MLD
17th March 2025, 03:24 PM
Does this qualify? Less than 1 day in low range. There was a time i went though a superpro bush every couple of weekends in low range. SP said they would stop honouring warranty on me because i was eating bushes too often. Went to a patrol style bush at the chassis end and that sorted my problem.

DazzaTD5
18th March 2025, 05:35 PM
Does this qualify? Less than 1 day in low range. There was a time i went though a superpro bush every couple of weekends in low range. SP said they would stop honouring warranty on me because i was eating bushes too often. Went to a patrol style bush at the chassis end and that sorted my problem.

Thats pretty ****, to me the bush part looks too thin.
I use "run of the mill" Terrafirma poly and they are as thick as the original rubber bush.

I dont hammer to customers that they need poly bushes bluh bluh bluh, mostly its all bull****. I tend to find big tyres, 35" and the likes to stop the wallow fitting hard poly bushes helps.
Yes you can get the odd Defender that eats out bushes but as a general rule the original rubber bushes can last a very long time.

Tins
18th March 2025, 06:37 PM
It’s always been that way on the forum. I can’t help it if people only look at one section of the forum (and some do), e.g., some only look at the section that refers to their vehicle model.

I know, Ron. I remember when the "New Posts" feature was added. I only said it was a pity, not that you were wrong.

Tins
18th March 2025, 06:40 PM
Does this qualify? Less than 1 day in low range. There was a time i went though a superpro bush every couple of weekends in low range. SP said they would stop honouring warranty on me because i was eating bushes too often. Went to a patrol style bush at the chassis end and that sorted my problem.

So, SP thinks their bush failing is your fault, not that it's unfit for purpose? Good to know.

MLD
18th March 2025, 07:46 PM
So, SP thinks their bush failing is your fault, not that it's unfit for purpose? Good to know.

In fairness to SP, i destroy a genuine style bush in the same amount of time. There are plenty of defenders running around on 35s, long travel suspension, low gearing and a heavy sals. They seem to get longevity out of bushes. For some reason that i haven't worked out, i destroy them. I'm certainly heavier than the comparable defenders i know with similar set ups. Weight must be in the negative column with the torque multiplication of lower gearing. I went with a shorter shock to limit travel in the hope to get more life from the trailing arm bushes. The cost of doing business.

POD
18th March 2025, 08:51 PM
I've found LRA's angled rubber bushes serve me very well, when I saw what at first appeared to be a stuffed bush I was surprised. The only other aftermarket bush I have tried in many years- and I can't recall the brand- was destroyed in one weekend. rubber similar in appearance to the genuine. I tried poly bushes in a few different vehicles decades ago and swore off them.