John,
Make sure ball joints are good, not sure just jumping on the bumper will be
sufficient. I just had a nasty surprise with an upper control arm ball
joint. I was hearing an intermittent thunk under the van and would also
jump on the bumper to check suspension and no thunk. All the ball joint
rubber boots were intact and looked normal. I decided to change all the
bushings on the front end just because of age and mileage and some were
definitely in need of replacement ( upper control arm bushings ). In this
process I discovered that one of the upper control arm ball joints had no
grease in it. The boot was intact and looked swollen with grease. It was
completely rusted. It must have been a defective from the factory. Anyway,
I'm sure that this was the source of my thunk. Good luck.
Rick Koller
'90, '91, '91

On Thu, Oct 15, 2015 at 1:32 AM, john <john@jhl.mgacoxmail.com> wrote:

> I am getting intermittent "clunk" from under middle of van
> while driving.  '84 Vanagon, 1.9L engine, automatic
> transmission.  "Clunk" not associates with turning as would
> happen with CV problem.
>
> Increasing occurrences of the"clunk."  Nothing obvious under
> van.  Had my Son jump up and down on front bumper while I
> locked at front suspension with wheels first turned full
> right and then full left. Nothing appeared loose.
>
> Got under middle of van.  Tried to push up on gas tank.
>  Seemed secure.
>
> Had Son drive van to end of driveway where the curb drops
> off more than most driveways would.  Had him run van back
> and forth over drop off.  No clunk.
>
> Any ideas where I should look next?
>
> Thank you,
>
> John
>