I have a 1998 Caravan ( regular length) that has a leak in the rear tailgate. It only seems to leak during downpours and doesn't during either a steady rain or being washed. The leak os on the passenger side and runs down the interior side of the van to the carpet.

I checked around the main rubber gasket that seals the tailgate to see if there were any leaves / pine needles that may be stopping up the flow or any visible tears or holes but didn't see any.

Any thoughts on how to chase this down and also potential fixes?

Thanks in advance

 

I don't know if this is the problem you are having.But here is a tsb.
SUBJECT: Backlight Water Leaks
DATE: Sep. 19, 1997
NOTE: THIS BULLETIN APPLIES TO VEHICLES BUILT AT ST. LOUIS (IDENTIFIED BY THE LETTER "B" IN THE 11TH CHARACTER OF THE VIN) JULY 14, 1997 THROUGH AUGUST 30, 1997 (MDH 0714XX THROUGH 0830XX).

SYMPTOM/CONDITION:
Some of the subject vehicles may have a marginal or partial bond of the backlight to the liftgate that may develop into a water leak.

DIAGNOSIS:
If there is a water leak at the backlight to liftgate bond, remove the screws atttaching the backlight side moldings and separate the moldings from the vehicle (the moldings retain the glass to the liftgate preventing a good check of the urethane bond). Try to separate the backlight from the liftgate by pushing very hard on the inside perimeter surface of the backlight, or try to pry the backlight from the liftgate with a trim stick. If the bond between the backlight and the urethane fails while pushing or prying, perform the Repair Procedure. If the bond between the backlight and the urethane does not fail while pushing or prying, use normal re-sealing techniques.