Series Ii Gs430 Sport Knocking Noise At The Rear

[eMJay]

I've got a strange knocking noise at the rear of my car and it sounds like it's predominantly the left side. My Dad thought it was the tools etc that are in the boot but I wasn't convinced because the knocking happens at slow speeds which aren't enough to make things move with enough force to sound as loud as it does. I removed everything anyway and as soon as I pulled off the drive the noise was still there. All I can tell you is it happens at slow speeds when I'm entering and leaving driveways that have a slight slope up to them, like the ones where you have to cross a path, when the car is twisted and flexing whilst steering, usually to the left. The sound doesn't happen in a straight line during normal driving or going over bumps in the road or speed bumps and I can't replicate it with the car stationary and bouncing the suspension.

I haven't jacked it up to have a look yet and will get the dealer to have a look when they've got it on the ramps for the service, but I was wondering if anybody here had any suggestions as to what it might be. It's annoying and doesn't sound good, but hopefully it's something simple due to the infrequency of it.