I've had a 'thud' on my rear suspension for some time - never been able to pin point it. Not Anti-roll bar links, nor anything catching, nor the suspension shocks as you can hit 'speed bumps' quite hard without any noise. The sound is more like something loose in the boot, and can be heard on uneven roads.
Had a poke about underneath, nothing loose, but the rear anti-roll bar rubber bushes looked 'old' and were slightly out of shape. Hmmm, hardened, I wonder. Checked on line, yup just £6 a pair (this idiot thought they came as singles so bought two). Before ordering, checked I could undo the four bolts for the brackets - yup the 18" breaker bar shifted them. Just collected the parts, and from getting the tools out, to putting away was just 20 minutes. Why didn't I have this brainwave before.
Suspension is now quiet as a mouse, road tested on the worse road in the area - ex cobbled road, with tarmac thrown on top. Now to get booked in for it's MOT.