Knocking (well sort of) noise from the rear

[Craig Rogers]

I've got a strange noise from the rear. It's only when stopping and starting at very slow speeds (like parking or traffic for instance).

It sounds like fuel in the tank moving back and fore. Does anyone else have this. It might not be, but that's all I can explain it as.

[Gsi3.2]

nothing loose in the boot or wheel well is there?...exhaust is on all it's hangers isn't it?..