1991 E34 M5 - Single Clunk over bumps Rear of car

[chazuno 7]

Hello: My first of what I hope are not too many questions. 1991 M5 is making a single clunk or mild knowing sound when going over medium bump or rut. I had her on the lift last week and the struts show now sign of leaking. The accumulator are about 10+ years old. Subframe mounts done about 4K miles ago. Pitman arms and sway bar links done at the same time.Car has been sitting for quite some time. Thank you in advance for your thoughts, consideration and support. Chazuno

Edited October 31, 2018 by chazuno

[d_a_n1979 2,786]

Welcome to the forums @chazuno

 

Stick your questions in the relevant E34 tech section further down the page and they'll get batter answers and coverage

 

This section is just for folk to introduce themselves to the forum etc

[chazuno 7]

Thank you very much for your assistance. I apologize to the crew and new members whom this section  applies. I will pay more attention. 

[amauvis 69]

Welcome I've seen the pics in the other thread, your car looks great

[stevenc3828 165]

Exhaust mounts on the back box stretch over time.

 

Could also be the shock top mounts and / or the rubbers that isolate the springs

 

i presume the self levelling fluid is at a sufficient level?

[chazuno 7]

Stevenc3828: Thank you very much. I have the top of the strut mounting exposed and we will be looking into top mounts. I will also bring up the rubbers that isolate the springs. The Pentosin ll is at the proper level and clean / fresh. Thank you very much for taking the time to give consideration and support to my issue.

[Zackpl 62]

I've had a similar effect on a rare few occasions always after lifting the car. Turned to be down to springs not sitting right in the rubbers pads, going away after spirited drive, ending with a loud clunk (indicating the moment where spring finally finds its place).