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Hi, I've tried just about everything that I can think of, and would be grateful for any help you can offer in diagnosing a rattle from the rear suspension.

Apologies for posting this here. I can't post directly to the suspension and steering forum because I'm a newbie, but hope it is not too much trouble to put it in the right place.

The rattle occurs on rough roads, but not necessarily on pot holes. It doesn't depend on speed, acceleration or breaking, and comes from under the car (ie not the top of the shock absorbers) in the vicinity of the rear suspension, and it is not possible to tell from which side it comes, even having sat in the boot. I have not been able to replicate the rattle when the car is stationary.

There is no play in the wheels (since replacing the top links). There is nothing loose under the car or under the luggage space, and there is no evidence of anything rubbing, or perished rubber. All suspension bolts are done up tightly.

I have replaced the top links (very badly worn), the roll bar links (not noticeably worn) and the roll bar bushes (corroded, but not worn). I have seen a post on another web site suggesting rear subframe bushes, but this looks like a big job (even the Haynes manual doesn't cover it) and a real pig without a lift, and wanted to take some advice before trying (not least on how to do it).

Any help or suggestion gratefully received.

I had a rattle on the rear end I was having trouble diagnosing, and turned out to be a broken clip that holds the brake pads
It had snapped in half and was rattling away

Plod, thanks. I've checked the brake components on both rear wheels, and there is nothing apparent to suggest this is the source of the rattle. All brake pads are firm, and there are no broken or loose pins or bolts.

I've also (again) stripped everything out of the boot, and sat in the spare wheel well with my wife driving. The knocking appears to come from just in front of the spare wheel well (where the sub-frame is attached).

I've also noticed that when driving beside a wall, there is little reflected noise from outside the car, and the knocking is mainly from inside the car. This would suggest that it is the body of the car that is being knocked against, and that it can only be the subframe doing the knocking.

Would this be caused by work subframe bushes?

jaylow wrote:but hope it is not too much trouble to put it in the right place.

No trouble at all , hope you get it sorted.

Had a rattle from back end of my d8 checked suspension,brakes and exhaust but it was still there past MOT with it but was driving me nuts turned out to be the gas struts that hold the boot lid open,they were worn at the ball and socket behind the lining at the topside of the boot space,got a couple out the scrappies problem solved.

Fuel tank loose?

Have you replaced the Anti-roll bar mounting bushes? I think you said you had? the drivers-side one is a pig to get at because of the fuel tank/filler neck.

If you've done all these bushings then it may point to the rear trailing arm bushes (have to be 'pressed' on a machine) I think the only good way to check is having the thing right up in the air and go around all the mountings with a big pry-bar looking for movement.

Oddly enough I've finally cleared the knocking from the back end of mine after many months of head scratching. I'm not sure if you mean this when you say you changed the top link but I'll leave it here anyway for anyone searching.

Number 13 here:


This was coming slightly more from the r/h side of the car. All the times I had the car jacked in the air and I couldn't find anything, I even ended up with some of the plastic packed out with cardboard Then we had it up on the 4-poster, the mechanic levered stuff about until he found a microscopic bit of play on the inner bush, seems it needed the weight of the car on it for it to become apparent.

Mine was due to the ARB bushes and the drop links - replaced both and its tightened the handling and no more annoying noises!

Thanks for all your help. I've found the source of the rattle, which was a set of worn anti-roll bar drop links, but not before I'd replaced the rear subframe bushes. I had assumed that the drop links would have been OK as they were replaced only six months ago, and hadn't bothered checking them thoroughly. I guess that's the danger of buying cheap parts on ebay!

Replacing the subframe bushes was an easier job than I had thought it would be. The old bushes can be prised out from above with an old chisel, and you can get access to the top of the subframe by removing the retaining bolts and relieving the tension on the spring, which I did by disconnecting the bottom of the shock absorber and removing the spring. I suspect removing the subframe altogether would have been difficult, but it is possible to let it drop a couple of inches to rest on the exhaust and fuel filler pipe, and get at the bushes from gap created in the wheel arch, which I did one side at a time.