Hi Dave. the common problem with water ingress on your vehicle is through the rear lamp clusters. To find out which one is leaking, get someone to shut you in the boot with a torch and a piece of dry cloth ( someone you can trust!!! ) and get them to play a hose around each light cluster in turn. This should identify the culprit. remove the offending cluster, about 4 nuts on the inside, thoroughly clean the bodywork at the mating surfaces, if you have IPA all the better. Clean the sealing gasket and the light cluster where the gasket touches, and run a bead of bathroom sealer around the lamp and the mating surface on the bodywork. ensure a continuous bead with no breaks. Fit the gasket to the body then the cluster to the gasket. Try not to move it about too much, a straight on fit is best. Tighten the mounting bolts evenly, but do not over-tighten. leave to cure and test with the hose again. Of course there is chance the boot/tailgate surround rubber seal leaks, test that when you are in with the torch. Replace the seal if leaking. Good luck.
Paul
February 2008
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