I want quieter suspension.

[Fonzey]

My car is bugging me, my rear suspension is noisy

I've got coilovers, and they're track focused coilovers so "because racecar" is the only explanation I can get from anybody.

In hindsight I bought the wrong suspension, but I'd still like to do whatever I can to quieten things down a bit.

I've tried all sorts, all suspension related bolts/torque has been checked, the rear struts have been dismantled and rebuild with nicely greased bits etc.

The noise I've got is like a light "clattering" only from the rear, the fronts are totally silent. I don't get any big clunks, just a constant clattering/chattering - very hard to describe. It doesn't seem to be provoked by bumps - I can hit a speedbump and hear silence, but then on a smooth-ish road I hear the clattering. It's almost as if big compressions are quieter than little ones.

I'm looking for ANY generic advice to try and quieten these down. One thing I noticed is that my front springs have got a rubber sleeve covering the coils at the top and bottom, but my rears dont:



Are these sleeves available anywhere to buy, although the top and bottom of my springs seems really tight and I'm not sure whether I'd be able to slide a sleeve over even if there is.

Any other pointers for quietening things down a bit? I understand they're intended for track use and don't have rubber top mounts - but I've been in cars with solid top mounts before and they've been silent. I'm seriously considering getting rid of these and buying the lower-end range of coilovers with rubber top mounts but I'd hate to a) lose out on the money I've spent and b) compromise on the performance.

Any help would be appreciated.

[PaulKemp]

Springs may be short you could try tightening spring platforms or buying spring assistors these take up slack when suspention is unloaded

[PaulKemp]

Not the rubber things
Proper flat metal coils
I think you can find them on Rally Design or Demon Tweeks web sites

[stevieturbo]

Drop links etc ok ?

Ive never used the BC's with the remote reservoir, but used a good few sets of the normal coilovers. Never had any issues with noise on them

[Fonzey]

Thanks guys, I've checked preload on the springs and droplinks (a tonne of times!) but there are other bits under there (lateral links, trailing arms, etc) which seem tight but could probably do with being stripped and bushings checked etc.

My main frustration is that people tell me "they're solid topmounts which transmit the sound into the cabin, so just forget about it" but for them to transmit sound, something must be making the sound in the first place! It sounds like something is loose/clattering somewhere, so the search goes on!

[PaulKemp]

Try backing off the dampers
I assume they are adjustable
Concider softer longer springs

[andyiley]

I had exactly the same (from your description) on my e36 after changing the rear bushes & calipers for upgrades (it too it a track car) and after lots of attempts at fixing found that it only happened when not braking. The sound was half way between a rattle & a clatter.

Try the following, identify somewhere where it is particularly noticeable, and then travel the same area both with SLIGHT left foot braking, and then with the handbrake dragging.

If it is like mine you will find with one or the other (or both, depending on your rear brake set up) the sound disappears.

With mine it was the rear disc pads (rather than hand-brake shoes) that were rattling.

These calipers did not have anti-rattle springs fitted, so I had to identify some that were close enough to work.

[Kozy]

Anti-roll bar bushings?

[one eyed mick]

Take the comp based stuff off and refit orig gear and the job will be sorted or wear a crash hat or ear plugs [ both] and it will go away

[The Wookie]

Aside from what you've already checked:

ARB droplinks (check for play, not preload, might be worth changing them anyway if the car has done plenty of miles)
ARB bushes
Top Mounts (again remove and check for play, make sure they're fitted correctly as I've seen them mounted upside down where they tap against the body on more than one occasion)

Also worth checking the front as sometimes the sound can travel in odd ways.

Failing that you may just have a faulty damper that's lost its gas pressure or is just over damped for whatever reason and is cavitating.

[Fonzey]

one eyed mick said:

Take the comp based stuff off

This is my ultimate fall back, but I'm not ready to accept it as a solution yet! I've had all sorts of knocks and rattles fixed on this car despite being told "it's a racecar, put up with it..." This one has got me beat, so far!

Thanks with the suggestions guys, ARBs/Links/Bushes were new earlier in the year - but all torque has been recently checked and bushings regreased.

Braking doesn't seem to manipulate the noises at all, so kinda ruling that out for now. Sounds are consistent across two sets of pads (I switch out for track days). Caliper brackets have all been checked for torque settings etc.

The car is currently with a suspension specialist having the alignment setup, corner weighted and damper's measured for optimum setup. I've mentioned the noises to them and they're going to give the whole setup a proper going over, hopefully finding something loose or damaged along the way. They told me that they've had BC coilovers in before which had lateral movement within the shock body - so they'll check that and advise accordingly.