knocking from rear....but what could it be?

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dom-1984-320i
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Post Thu Oct 19, 2006 12:14 am

hi guys,

i have a 1984 320i auto, when breaking i can some times hear and feel a slight knocking coming srom the rear of the car. At first i thought the spare whell had come loose and was moving under breaking, complitley emptied the boot and still happens every now and again. Any ideas, i just hope its nothing major, any ideas?

cheers
TW166Y
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Post Thu Oct 19, 2006 12:28 am

sounds like bushes to me mate, quite common 8)
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Brianmoooore
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Post Thu Oct 19, 2006 12:39 am

Far more common to be a rear damper top mount.
Look in the boot. Pull in the sides of the boot liner.
On top of each wheel arch is a rubber cover - pull them off.
If you can move the threaded rod in the middle at all then the mount is shot.
Replace with ones for an E46 cab.(same price, direct fit, stronger)
TW166Y
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Post Thu Oct 19, 2006 12:51 am

Brianmoooore wrote:Far more common to be a rear damper top mount.
Look in the boot. Pull in the sides of the boot liner.
On top of each wheel arch is a rubber cover - pull them off.
If you can move the threaded rod in the middle at all then the mount is shot.
Replace with ones for an E46 cab.(same price, direct fit, stronger)
good call dude, totally forgot about them babies
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dom-1984-320i
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Post Thu Oct 19, 2006 11:51 am

Brianmoooore wrote:Far more common to be a rear damper top mount.
Look in the boot. Pull in the sides of the boot liner.
On top of each wheel arch is a rubber cover - pull them off.
If you can move the threaded rod in the middle at all then the mount is shot.
Replace with ones for an E46 cab.(same price, direct fit, stronger)
hey Brian,

i have just replaced the both rear top mounts only a couple of weeks ago, could it be the bushes, and is it a big job to fix?

Cheers
TW166Y
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Post Thu Oct 19, 2006 6:29 pm

try it mate diy them 8)
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surj
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Post Thu Oct 19, 2006 6:43 pm

back bushes or IE (subframe mount bushes) are a complete pain in the arse without the tool because you have to burn them out with the tool takes around 15 min a side bushes from gsf are about Ԛ£20 garages normally want between Ԛ£60-Ԛ£100 to fit them
old_skool
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Post Thu Oct 19, 2006 8:13 pm

I wouldn't recommend burning them out with the subframe in place 8O

Sounds like a damned risky business to me. Better of dropping the subframe out and doing the subframe bushes on the bench and also do the trailing arm bushes at the same time. That way will take you longer, but certainly won't cost a whole lot more and be a damn sight safer and a more thorough job. It isn't rocket science either.

Either that or bite the bullet and be at the mercy of your local garage.
try it mate diy them
Go for it. :D
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Brianmoooore
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Post Thu Oct 19, 2006 8:52 pm

Still check the damper mounts again.
First rule of fault finding: Chief suspect is the last thing you did.
dom-1984-320i
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Post Fri Oct 20, 2006 6:47 pm

Brianmoooore wrote:Still check the damper mounts again.
First rule of fault finding: Chief suspect is the last thing you did.
Will check them tomorrow. As for DIY not really my bag, i would probably do more harm than good, will get the garage to check it out.

Cheers for the advice guys