somthing weird at the back...

[jaydom]

Hello everybody,
i'm going to explain what is my problem in a correct english, but as i'm french, excuse me in advance...
So i own a 4.5 cerbera from 2001. Very nice, powerful car. What a pleasure !
I went on holidays last week to the Alpes.
So, a lot of turns, faster or slowly...
The problem arrives when i go slowly...
And many times the car had the same problems. It happened to me once or twice when i was parking the car ; when i get out in reverse gear, no problem ; but as fast i put the first gear, with the wheels not straight (imagine i go on the left or the right compared to the way i was going in reverse) i feel like a banging at the back.
When i was driving on mountain roads, it happened quite ten times.
I'm engaging the turn in second or third gear ; notice i change the gear before the turn.
When i get out of the turn, there's a banging and the car seems like floating at the back for one second.
The car is not dangerous, but it's really uncomfortable cause you can think that you are loosing a wheel.
What do you think it could be ?
Hydratrak ?
I lift the car and everything seems to be perfect : the exhaust are well fixed, the wheels too.

Many thanks in advance !

Cheers

Jerome

[high52kojak]

It sounds like the differential, especially if its when you are turning, creating a speed difference between the two wheels.

But, have you got identical tyres on both sides of the car? This has been known in the past to cause banging issues with the diff if the tyres are different, because of the different rolling diameters of the wheels causing the speed difference between the wheels.

[Mad Mark]

high52kojak said:

But, have you got identical tyres on both sides of the car? This has been known in the past to cause banging issues with the diff if the tyres are different, because of the different rolling diameters of the wheels causing the speed difference between the wheels.

Yes this was me (hangs head in shame lol)
One of my tyres was worn compared to the other. While traveling up the road the car would basically drift to one side and release with a bang. What was happening is the Diff was 'thinking' the car was wheel spinning, as they had a different rolling diameter, so locked up causing the car to drift and then the Diff would break free with a heavy bang.
This 'bang' also occurred during certain parking maneuvers.
If the tyres are fine then also worth checking the diff brackets. The central one at the rear is known for breaking sometimes not visible until you remove it and then it falls in to two pieces.

[high52kojak]

You mean like this:


Its worth checking this, its a known weak spot.

[JensenA]

Jaydom - Get the car up on ramps, and check the Diff mounting brackets. there are 2 at the bottom front of the diff, and one at the top rear.

[jaydom]

Ok

Many thanks for all your answers !!

So fast and so professional ones !

I will check all the points

Kind regards

Jerome

[fatjon]

Also check the rear anti roll bar rubber bushes which caused a very similar noise on mine. They are very cheap and take only a few minutes to change. Rear drop links can make unpleasant noises and break quite frequently. Also cheap and easy to replace.