Rear 'clunking'

engine · July 9, 2019

I've had an issue with the rear passenger side being a bit 'knocky' since I've had my RX400h, but I recent went down a rougher road and it is now decidedly worse.

Almost a year ago I replaced all the ARB bushes and links, thinking it was that kind of noise, but it remained. The MOT didn't pick anything up.

I took the strut off to check for anything obvious, but couldn't find anything. The play only seems to be at the 12 o'clock position, and I can't determine what is causing it. It seems, from videos I've made (see below) filming behind whilst I manipulate the wheel, that the strut moves with the noise, suggesting it isn't likely to be a floating wheel issue (wheel bearing, for example). The wheel bolts have been removed whilst I removed the strut, replaced, and everything appears to be nice and tight until the wheel is back on.

It is pronounced when that wheel goes over bumps, and the knocking reverberates, leading me to suspect it could be shock absorber linked - I just can't see how. Any ideas/knowledge/experience is welcome.

https://imgur.com/a/RJqAwtF

engine · July 20, 2019

In case anyone ends up with the same in future, a replacement shock absorber solved the issue.

Despite not giving the usual symptoms (I assume due to the weight of the RX), the shock absorber had completely failed - with the spring off, the piston could be moved its entire range, and the 'clunk' was essentially a bit of slack at either end of this.