Mysterious "Clunk" from rear - RX 400h

[rynd2it]

My 2007 RX400h has developed a mysterious "clunk" from somewhere in the rear and neither I or the local Lexus Service Centre can find anything wrong.

Over the past three days they have:

Replaced the shock absorbers. Removed all rear interior trim, spare wheel, anti roll bar and tools and anything else moveable. They have pried away at all the suspension moving parts and can find nothing loose. They even dropped the rear subframe and refixed it. In all they spent over 12 hours removing stuff then driving around with someone in the back listening. We've searched the car for loose objects etc.

Nothing, noise is still there, more noticeably when driving slow, around 20mph, especially on sharp little bumps like concrete joins, the sound is exactly like a shock absorber with a very loose mounting.

Anyone else ever experienced anything like this and if so did you cure it?

 

 

[NemesisUK]

Not experienced it myself but have you checked the security/tightness of the back door(tailgate) lock?

[rynd2it]

17 hours ago, NemesisUK said:

Not experienced it myself but have you checked the security/tightness of the back door(tailgate) lock?

Naturally, and if it isn't tight the dash warning light stays on

[Steve]

18 hours ago, rynd2it said:

My 2007 RX400h has developed a mysterious "clunk" from somewhere in the rear and neither I or the local Lexus Service Centre can find anything wrong.

Over the past three days they have:

Replaced the shock absorbers. Removed all rear interior trim, spare wheel, anti roll bar and tools and anything else moveable. They have pried away at all the suspension moving parts and can find nothing loose. They even dropped the rear subframe and refixed it. In all they spent over 12 hours removing stuff then driving around with someone in the back listening. We've searched the car for loose objects etc.

Nothing, noise is still there, more noticeably when driving slow, around 20mph, especially on sharp little bumps like concrete joins, the sound is exactly like a shock absorber with a very loose mounting.

Anyone else ever experienced anything like this and if so did you cure it?

 

 

i bet the dealers charged a pretty penny for all those hours?

[rynd2it]

4 minutes ago, Steve said:

i bet the dealers charged a pretty penny for all those hours?

They were very generous, they were not going to give up until they found it but eventually they had to as they ran out of ideas. I won't name them for obvious reasons