Things that go bump in the night - help!

Hi folks,

I have a late S3, 88". When I drive over undulations in the road, I get a strange bumping noise and associated knock on the underside of the driver's footwell.

I've had the truck up on ramps to look underneath and everything appears to be tight and as it should. Has anyone experienced this phenomenon elsewhere and if so, have any suggestions on now it can be cured?

Exhaust?

Check u-bolts,mine had a bad knock and it was the u-bolts that were loose so the axle was rattling about on the spring. Also could be a worn spring/chassis bush.

I repaired the exhaust hanger that was rusted through a few weeks ago, so am pretty sure it's not that. I'll tighten the U bolts today to see if they have worked loose (we fitted para's not so long ago, so they could have worked loose). Failing that, it is in for a service next week, so I'll ask them to check the bushes.

It is really quite annoying!!

Not the hangers - they were tight as hell. Any other thoughts?

It almost feels like there is something heavy swinging around underneath. I've been under the truck this afternoon, wiggling and trying to move everything, but it all seems really tight. Is there anything on top of the gearbox that can move around?

It's kind of a dull, lazy "donk" and I can feel the clunk through my clutch foot when it's resting in the floor.......

gearbox mountings weak?

crashbox said:

gearbox mountings weak?

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Can you feel the clunk through the gearstick? If so, :5biagree::5biagree:

Oldseadog said:

Can you feel the clunk through the gearstick? If so, :5biagree::5biagree:

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No. Not a sausage. There are no other adverse sounds / vibrations / occurences other than this "donk" and the associated knock through my left foot.

Most wierd!!!

schmalex said:

No. Not a sausage. There are no other adverse sounds / vibrations / occurences other than this "donk" and the associated knock through my left foot.

Most wierd!!!

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If you have no other weird vibrations, sounds or occurances i think there might be something seriously wrong with your Series :s

It's normal to have random happenings as you drive

Does it occur randomly or at the same time as you are going over bumps? I had strange and quite violent knocks only in the rain when cornering!! Traced it to partially siezed spring bushes.

It occurs every time I go over an undulation in the road, or a bump, or turn a corner such that the body leans ever so slightly.

It is somewhat intermittent in as far as I thought I had cured it by replacing the rear exhaust hanger which had rusted through & was allowing the exhaust to swing free and knock against the chassis. However, 3 weeks later, it is back & going "donk", with the accompanying reverberation through my foot on every undulation in the road.