judder on take off?

[connoisseur]

1990 325i 4 door saloon. Occasionally when moving off I get three or four short thuds. The noise then disappears and may not happen for a day or so.

It feels like it is coming from low down the rear - at first I thought I had something loose in the boot but no. Otherwise the car drives fine. This evening I had four adults in and it was happening more often.

Welcome any ideas of what it could be.

Thanks

C

[dicko]

Is your diff wobbling around i wonder may be the mounting is lose or the bush worn

[fuzzy]

possibly the prop centre bearing has gone,cheap and easy to replace if it is. jack up the car and look to see if the rubber bush has torn away from the bearing.is it a knocking on the floor just behind the front seats? it tends to knock on acceleration.

[tari]

Where under the car would you find this? as i think i have the same problem

Cheers Tee

[1an]

trailing arms bushes? diff bush? possibly any of the bushes as they may well be excessivly worn

[fuzzy]

Where under the car would you find this? as i think i have the same problem

Cheers Tee

the prop centre bearing is roughly half way along the prop about in line with the front of the back seats and is bolted up to the floor.

[connoisseur]

possibly the prop centre bearing has gone,cheap and easy to replace if it is. jack up the car and look to see if the rubber bush has torn away from the bearing.is it a knocking on the floor just behind the front seats? it tends to knock on acceleration.

Fuzzy that is exactly what it sounds like, cheers I'll get it sorted. Thanks guys for all suggestions. I did get all the bushes checked, recently. Casn you walk through how I replace it?

Regards

C

[fuzzy]

possibly the prop centre bearing has gone,cheap and easy to replace if it is. jack up the car and look to see if the rubber bush has torn away from the bearing.is it a knocking on the floor just behind the front seats? it tends to knock on acceleration.

Fuzzy that is exactly what it sounds like, cheers I'll get it sorted. Thanks guys for all suggestions. I did get all the bushes checked, recently. Casn you walk through how I replace it?

Regards

C

mine is a different set up due to my custom prop and is a nightmare to do but a standard e30 prop is easy to remove iirc but will need someone elses technical input to confirm.a new bearing is under £20.

[connoisseur]

Thanks again fuzzy, much appreciated

[old_skool]

Just a note to say that you will need to remove the exhaust and tunnel heatshield to access the propshaft centre bearing on a standard E30.

Once all this is out the way then it's a reasonably easy job to do though. Make sure you preload the new bearing by moving it towards the front of the car under gentle resistance before nipping up the two bolts that hold it to the chassis (5-6mm). Use the search function - there's info on how to do it on here if your unsure.

Good luck.

[connoisseur]

Just a note to say that you will need to remove the exhaust and tunnel heatshield to access the propshaft centre bearing on a standard E30.

Once all this is out the way then it's a reasonably easy job to do though. Make sure you preload the new bearing by moving it towards the front of the car under gentle resistance before nipping up the two bolts that hold it to the chassis (5-6mm). Use the search function - there's info on how to do it on here if your unsure.

Good luck.

Many thanks old skool - very helpful that.

C

[tari]

Cheers Fuzzy

[dodgem]

Ahah! That could be the noise coming from the rear of my car too

Had the rear subframe bushes replaced recently, and checked the diff mounting bush and it was fine, but i get a single knock usually if i accelerate in 1st or 2nd. Also been getting a worrying few knocks on a particular left hand bend onto a side road that drops sharply downhill... so the rear left wheel unloads a fair bit. Is that likely to be the same thing? Or anyone got any other suggestions for that noise?

Cheers