Carver Truma Mover 2 loose bolt

I have a Sterling Eccles Moonstone caravan (2007) with a Carver Truma Mover 2 motor fitted. Recently I used the van for the first time this year and noticed a clunk followed by a metal on metal squeak for about 1 second from the offside wheel/motor mover.  I have checked the wheel bearing, brakes and wheel nuts. I have lubricator the mover. The odd noise is still present when using the mover, particularly on corners.  No odd noises noticed during towing.

there are two small (M5 bolts just above the main engagement slide bolts with nylock nuts on the far side..  These seem to hold the two plates either side of the spring together. I note the bolt furthest from the wheel is very loose - around 5mm of free play. I don’t know if this is correct or whether this bolt should be tight?   When the mover is not engaged the back of the electric motor can be moved about 5mm from side to side.

I contacted Truma but the unit is too old for them to advise. 

Any ideas welcome

thanks

Martin