Knocking noise from rear of car

[blizeH]

Hi,

Whenever I go over some bumps, or go around a corner etc there's a knocking/bumping noise coming from the back of the car. I've got a couple of people to sit back there and have a listen, but everyone comes up with conflicting guesses; usually involving the boot or the door.

I've tried...

- taking everything out of the boot, and making sure the spare wheel tools are all fitted okay and not banging around.

- taking off the parcel shelf

- wobbling the doors

- pressing down on the rear of the car to check the suspension

... but still no closer to finding out what the hell is making the noise. It sounds to me like it's coming from the rear of the car, but high up, but surely there's nothing there that could make a noise?

I'm a bit confused to be honest, and just wondering if anyone else had any suggestions or things to check.

Cheers!

 

[jake]

rear axle beam bushes go round 50k iirc

jake

 

[lc_allan]

Rear top mounts on the suspension?.

 

[flares]

Check all your wheel nuts are tight

 

[blizeH]

Many thanks guys, just checked the wheel nuts and they all seem okay, pardon my ignorance but is there anyway I can check the rear axle beam bushes and rear top mounts on the suspension myself? I've got no problems taking it to a garage, but if I could at least go someway to diagnosing the problem then that'd probably be a good head start.

Cheers

 

[DannyC87]

Give your exhaust a good wobble from the back of the car; see if it is hitting a heatshield or something.. thats what my knocking noise was.

 

[blizeH]

Good shout that, just gave it a wobble and no noise, dunno why I didn't think of that before though, cheers!

 

[andycupra]

shock top mounts of that the shock has gone would be my guess.
if the shock has gone it can seem like a fairly clear knock when going over bumps.

 

[blizeH]

Sounds quite likely, thanks - I'll look into that too.

Is there anyway of checking these things myself by the way? I wouldn't really know where to start... cheers

 

[smivvy]

Does the car shake a little when driving? Push the rear wheels (or even kick them) and if there is substantial movement in the rear wheel then it will most probably be the rear axle bushes. But generally with a knocking it could be rear shocks or springs

Don't you just hate knocks and rattles. Just had a high pitch rattle develop behind my dash. It's driving me slightly crazy or at least just a little more than I am now

 

[cruising03uk]

are these rear axle bushes common i never heard of it before is it a bit job hours wise?
take it that powerflex do some upgraded bushes?

 

[flappy]

Takes around 4-5 hours to change the bushes. There doesnt seem to be much point using powerflex bushes on the rear a road car (has been covered a lot on MKIV forums)