This isnt for a 400 but should still be relevant. I have a windshield leak on my 18 Acadia. What do you guys recomend? I've tried getting sevral glass places out to repair it but keep getting the oh were busy or oh damn we forgot line. I've never had to repair a leak like this before so I'm kind of clueless. I know the area that it is leaking so that helps. I just don't know of a good sealant to use.