Both windows on my SLK230 leak. I replace the window molding every 2 years to fix it. I am looking for the cause of the seal failures. Does the force at which the hardtop compresses the seal contribute to the problem?
It’s impossible to guess without seeing the old neoprene after it’s removed, but yours sounds like a good theory.
Has the car ever been in an accident?
What windows are leaking? Side, front, back??? Is it a convertible hardtop? Who is replacing the the seal? Maybe a good auto glass shop can find and correct the problem.
Some designs just lend themselves to leaking. If I think back on all the rubber sealing pieces I have replaced (and I replaced a lot for GM) I can not say that the reason for replacement was visible to the eye in 99% of the cases. Big with GM was any rubber piece from a Corvette,Cavalier, Camaro and the door seals for full sized pickups (also the seal for windows next to the jump seats) Nothing ever really stuck out when examined by eye.
My dad used to have problems getting his convertable tops to keep a good seal. Of course, he used to put his oversized, overstuffed golf bags w/the fancy golf carts in the back seat lying on the convertible roof…and occasionally start to raise the roof, foregetting they were there.
Do you golf?