Noise when driving over speed bumps

[tashtego]

I am getting a 'metally' clunk from the rear suspension when driving over speed bumps. It is louder when the car is loaded and/or there are passengers in the back. The exaust seems solid enough and the rear anti roll bar seems ok, mountings are in place and the bushes have little or no play. The shocks are new and the car is a 3rd Gen KZ-TE with 128000 Kms on the clock ( but original mileage could be higher). I have tried standing on the rear bumper and pushing down on the rear but that doesn't replicate the noise ( maybe not enough weight?).

Also there is a noise when cornering slowly on tight uphill hairpin bends, when the wheels are not level, so to speak...Also if offroading on very uneven ground, when one of the rear wheels is almost off the ground... Sounds a bit like metal being stretched/bent, it stops as soon as the road is flat again.


Any suggestions?

Cheers

[marcdtr]

Check the rubber bushes on the shocks

[BUSHWHACKER]

Broken anti roll bar bracket?

[TeaMonsta]

If your spare tyre is mounted underneath, it's not that rattling about, is it? Needing to be wound in properly?

[tashtego]

Thanks for the ideas but :

- mine has got the'spare wheel carrier' thing
- the ARB brackets are intact
- the shocks' bushes are in place and tight...

I' ll have another look in daylight tomorrow

:O)

[muddle]

Jack the back up slightly then check the arb links. Sometimes you need to remove the strain on them to check, mine are solid until jacked up, rattle like hell.

[Wolfracer]

I've never heard metal being stretched before... and metal is normally quite quiet when bent, so...
you said originally it "clunks" which indicates a sudden release of pressure.
So what's releasing?
ARB
Shocks - my old car clunked under certain conditions as the angular mount of the shock would cause a bind and then release... I don't think this is the case with yours as the Surf mounts are pretty much up and down...
Diff issue?

[tashtego]

I see, I will jack it up and check for play on the brackets...the noise you hear when one rear wheel is almost off the ground is difficult to describe: indeed, as you say, metal being bent doesn't really make any noise, this is more like the sound of a system under strain, bit like when you apply the brakes on a bicycle with dodgy brakes.
It might be related to the clunk you hear over speed bumps, or maybe not. I don't remember my old 2.4 surf having any similar issues, despite having old shocks and being altogether more tatty.

Cheers

[tashtego]

two fat blokes

Ok, jacked the car up both sides, no play in arb, all feels pretty solid. Got two fat blokes(me being one of them) to stand on rear bumper and push down on the rear, with a skinny, mechanically minded young chap lying underneath, not a sign of the metallic clang. But by putting a few brricks down on the drive and driving over them, you hear it clearly, coming from the rear axle, driver side, seems to be coming from somewhere near the wheel...?? If it was a suspension issue shouldn't it be audible with the car stationary as well?

Let me know if you have anymore suggestions, otherwise I 'll keep driving as normal and see what happens, if anything...

Cheers and thanks

[muddle]

Rear tie rod bushed/mounts.

[J i m s t e r]

My Saab was exactly the same, but clunking at the front. Was a tie-rod.

[BUSHWHACKER]

........ If it was a suspension issue should't it be audible with the car stationary as well?

No.
You can't replicate normal suspension movement by jumping up and down on the rear bumper with fat people in the truck!!!

Things you need to check are: (with an empty truck and with axle stands under the chassis so the axle can droop)

ARB bushes/brackets, thats including the ones on the axle and the end links.

Damper bushes, top and bottom.

Axle control arm bushes, top and bottom.

Panhard rod bushes, both ends.

Check them thoroughly by levering, pushing, pulling twisting etc, not by just looking at them.

Also, check that the jack under the rear seat is secure and not bumping around.

[tashtego]

ok

Thanks guys, I'll put the truck up on the ramp at a tyre place near here and go through the various bits as suggested,"Bushwhacker style".

My son kept telling me that the "fat blokes in the back" approach was a non starter!!

Cheers for now

[marcdtr]

Are the rear shoes worn metal to metal on one side? or a spring failed inside the drum

[tashtego]

I'll look into that too as soon as I have a moment,
cheers!