Bongo Fury

i think ive read on here about the back door being adjusted by the rubber things half way up on each side, is it true? and how do they stop the door knocking when i go over a bump, or if i grab it when its closed and pull it makes the same noise, or was it all a dream like dallas,(thats a tv programme from way back, with a very sketchy story, if your a young un and thinking whats dallas?)

but basically how do i adjust the door to stop the knocking?

not really looked at them before but do they adjust by twisting them because they are on threaded bolts ?, so they can be moved in or out to touch the inner side of the tailgate ?

it took me ages to find out that it was my back door thumping, and how to stop it, i tried all sorts to stop it all to no avail,then i just loosened the said parts and gave them a slight twist,so the tennon rubbed on the mortice, and its been good ever since.
or it may just be the lock catch on the bottom edge that needs loosening and sliding inwards to make the door shut a little tighter.
these are the only ways to adjust it,as there is no adjustment at the hinge end of the door.