Knocking at the back

[Jeronimo]

Long time and no need to consult the forum    but now I do. 

Legacy 2.5 Auto, 59 reg and 69k miles.

Regularly serviced and MoT'd though I have only done about 9k miles since purchase Jan 2014.

Recently it started producing a KNOCK whilst moving.  This can happen when just about rolling forward and/or at any speed.  It hardly seems related to any particular bumps in the road.  I can go over several and no KNOCK, then something gentle and it goes KNOCK!

I've had it on a ramp several times.  I have replaced antiroll bar drop links front and back.  I can see no loose connections of subframes to body, no broken road spring, nothing which feels loose or with play.  It is not a transmission fault.

Any ideas??   Could it be a shock absorber internal problem?  There's nothing loose in the boot.

Thanks for any advices.

Jerry

[GeoffLeggy]

My first guess would be a bush but yes there is the possibility it's shock related.  If not the shock itself then maybe a top mount.

[Jeronimo]

Ah!  The top mount, could be, I have not inspected that closely.  Thanks.

[Jeronimo]

Well, it weren't knocking at the back, it was the front.

One of the recently fitted roll bar droplinks had come loose.  A quarter turn locked it up again and knock was gone.

[GeoffLeggy]

Least you found it .