Knock when touch brake in Reverse

[phatbloke]

Hi
I havent had my 97 Legnum too long and have begun noticing a knock noise when i first touch the brake when in reverse. It only generally happens once until i go forward again then once in reverse it will happen when i touch the brake.

The car was totally checked out by the AA before purchasing and nothing could be found INSERT INTO post VALUES (apparently this noise was mentioned to them before checking); I have heard someone say something about a floating handbreak or something that may cause it but im not sure.
Has anyone else noticed it or have any ideas what it may be.
Cheers

[zedy1]

wheres the knock sound come from front rear

[phatbloke]

seems to be from the drivers rear wheel or at least near the rear

[-LegnumVR4-]

Could be the rear subframes diff bushes? Friend had something like that before.

[Freddy]

I have noticed this knock in a few cars that I have driven, when you reverse then brake. I have also noticed it when you go forward after reversing then brake for the first time. I put it down to 1mm play in the two bolts holding the calipers on that are allowing a small amount of movement.