Rattle from the rear

parabolica · Post by **parabolica** » Fri Jun 15, 2018 3:15 pm

When driving over harsh surfaces or broken road, there is a sound from the rear (both sides) - sounds like two small stones rattling around in a tin can; it goes away on smooth surfaces. I was concerned it was the springs, but I checked them today and both are fine. It's hard to replicate the sound whilst the car is stood still; closest is if you shake the exhaust, it sometimes taps on the bracing/heat shield - I checked everything and it is good and tight, i.e. no heat shield rot/hanging down on a hot exhaust etc.

The only other thing I can think of is the brake caliper retention/anti-rattle springs. I replaced the discs, pads and shoes a few weeks ago and the clips initially came out fine, but when we went to put them back in afterwards there was zero tension in them. Both clips looked identical in profile, but when you slotted them into their holders they would just fall straight back out. We bent them to try and put some tension back and they seemed to clip into the caliper nice and tight; but now I think these might be the issue as I tried to take one out, and it came out by just pulling on it rather than having to use a screwdriver/leverage.

Before I go ahead and order replacements, can anyone else think of anything else that it might be? I'm just having trouble imagining how the caliper/pads can rattle but obviously those clips are there for a reason.

mr wilks · Post by **mr wilks** » Fri Jun 15, 2018 9:08 pm

Backboxes have been known to break hanging brackets so worth getting underneath to check both are intact

charlie8 · Post by **charlie8** » Sat Jun 16, 2018 12:26 pm

Drop links ? look very carefully, I had to look very close to see the crack

Rock the hell out of the car at the rear and see if you can re-create the sound, then get under and pull the anti roll bar around etc

If it is, just £14 ....

parabolica · Post by **parabolica** » Sat Jun 16, 2018 1:55 pm

Thanks guys, did both of those things yesterday and couldn't find anything, although I might take another look at the drop links. I checked the exhaust hangers and they all looked in decent shape, and you really had to shake the exhaust around to get it to make any kind of noise, so discounted that. Rocking the car doesn't reproduce it. Reason I'm thinking it might be the anti-rattle clips is the sound is quite tinny and rattly (if that's even a word) whereas droplinks would be more of a knocking noise I think? I'll have a look anyway.

firebobby · Post by **firebobby** » Sat Jun 16, 2018 3:18 pm

Are you sure it's coming from the rear, I had a clicking sound coming from under the dash on rough or uneven surfaces. Turned out to be the brace bars in the engine bay, nipped up the nuts and no more noise.

parabolica · Post by **parabolica** » Sat Jun 16, 2018 4:03 pm

It's definitely the rear; just been out today with the top down and it's as clear as day that's coming from both sides, around the hub area, hence my theory that if the anti-rattle clips have failed, there is bound to be a rattling noise! Going to order the clips now; hopefully that'll fix it!

greg81 · Post by **greg81** » Sat Jun 16, 2018 6:21 pm

I had this exact problem

My rattle clips were missing completely? Can you move the caliper around by hand?

charlie8 · Post by **charlie8** » Sat Jun 16, 2018 6:29 pm

Worth a punt, although they should not have lost tension just by being prised out, seems a bit odd, are you sure they went back in correctly or back holder is rock solid.

Mine took plenty of force to push back in

Suspect its the pads/calipers rattling around - as its both sides

parabolica · Post by **parabolica** » Sat Jun 16, 2018 9:11 pm

Pretty sure I was re-applying them correctly; there isn't exactly much room for messing it up when you've fitted new discs/pads. The clips are still present and in their holders, but I can simply remove them by hand by pulling on them which isn't right. Have ordered new clips; fingers crossed they do the job.

adam1985 · Post by **adam1985** » Sun Dec 16, 2018 10:55 pm

Did this solve the rattle? Got a similar noise on mine at the minute, just started this week

ph001 · Post by **ph001** » Mon Dec 17, 2018 8:27 am

The simple way to test this is to see if the rattling stops under light braking, if it doesnt then the problem is elsewhere.

Don’t forget the oem rear springs are notorious for cracking which usually results in a 1-3” piece rattling around at the bottom of the spring holder.

patriot66 · Post by **patriot66** » Mon Dec 17, 2018 9:15 am

Brake backing plates can corrode and rattle. Handbrake shoes/assembly worth checking also. I'd start with 2 new clips on the calipers first though.

parabolica · Post by **parabolica** » Mon Dec 17, 2018 7:53 pm

I was an idiot. I had refitted the clips incorrectly, and they weren't tensioned over the caliper like they should have been. Car was in to the local specialist to have something else looked at and I mentioned the rattle; he took one look at the wheels, looked back at me and said with a straight face "your clips are on wrong". Felt like a prize pillock; even if I had taken 10 seconds to compare to the front clips I would have noticed...

Anyway I now have a spare set of anti-rattle clips if anyone wants them! Luckily they were only a few quid.

adam1985 · Post by **adam1985** » Mon Dec 17, 2018 10:44 pm

ph001 wrote: ↑Mon Dec 17, 2018 8:27 am The simple way to test this is to see if the rattling stops under light braking, if it doesnt then the problem is elsewhere.

Don’t forget the oem rear springs are notorious for cracking which usually results in a 1-3” piece rattling around at the bottom of the spring holder.

Mine does stop with light braking. Pushed the clips through the wheel and they seemed to be firmly attached.
Wonder if it's a loose handbrake shoe or something?

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