Soft Suspension?

Forum: 

Hi everyone I haven't been on the forum for some time, I've just had another MOT and passed again with only one miner note. Slight surface rust on one of the brake pipes.
I wonder if anyone can help though, the suspension is a little soft. When someone is in the back going over a bump theres a clunk noise from the back. Any ideas for stiffening the suspension up? I have spring assisters (rubber ones). It's a YRV Premium.:? Unknw Thanks Dave