The windshield gasket on my '99 HD was clearly needing attention. I purchased a replacement gasket from Bus Depot. After a few questions posted to the forum I learned from our resident experts that my current gasket on the RV was not the correct one as well as learned the correct way to install the new one. It was pointed out that usually replacing the gasket is done when a new windshield was installed but I decided to give it a shot to see if I could replace the gasket without removing the windshield. In the process I learned a few things.

  1. To be technically correct I will refer to the 'gasket' not as a gasket but as the windshield molding. The windshield is installed via 2 separate installation 'activities'. First the windshield is glued with some sort of urethane glue to the body of the vehicle. This is the actual water tight seal that keeps water out of the cab and bonds the windshield to the body.

  2. The second part is the molding .This molding is mostly cosmetic. Some web sites refer to this molding as trim.

  3. Pulling the existing molding off and I could see that under the molding is a channel to allow water that gets behind the molding to drain out around where the wiper arms are attached and then drop through holes to the ground.

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  4. After peeling off the molding I saw a lot of dirt and gunk being held there, potentially restricting the flow of water down the channel and out of the holes. Once all the molding was pulled off you can clean out the channel that goes all around the windshield with a garden hose.

    5. To remove the adhesive used to hold down the molding I first tried mineral spirits. That didn't work well so I tried Acetone. This softened the stuff but still didn't make removal easy and I think that is dangerous to use on paint (may remove it). In the end I just used a razor blade and tried to get as much off as possible without cutting into the paint which would expose it to future rusting. In the end I removed all of it with the mineral spirits however I don't think this is necessary. If a small film of the old adhesive is left I don't believe it would be an issue. From what I read on the web, professional window installers do not remove every last bit of adhesive before adding new adhesive when they replace the molding.


  5. After everything was cleaned (the photo is not before it was cleaned) I snipped off a piece of the new molding and tested that it fit all around the windshield. (The new molding from Bus Depot has about an extra foot of length so this was OK to do).


    6. The molding from bus depot already has an adhesive in it but you need to purchase more adhesive to use during the installation process. The reason for this is that the molding only grips the glass in a very small area. As the molding goes around the corners (especially at the top and bottom of the windshield) it wants to pull away from the glass because of the extreme bends and angles. By putting on this extra adhesive as the molding is fitted the molding is held in place as the adhesive cures.

    Here is the adhesive I purchased on Amazon.
  6. Starting at the bottom, put about 1 foot length of adhesive on the molding and the vehicle. Wait until it gets tacky then push the molding into place. As you go around the corners use packing tape to tape the molding down while the adhesive sets. I found packing tape held very well. I left the tape on over night before removing it. One tip that might help later cleanup would be to put painters tape around the sides and top so the extra adhesive that squeezes out won't need to be cleaned off later as one could just pull the tape. I didn't do this but wish I had. To clean off the adhesive I used mineral spirits.

    7. Here is the final result.




  7. One last thought.
    Putting this on was a bit of a pain in the..... A better option might be to buy the molding and then go to an automotive glass place and see if they can install it for you. If it is a few hundred bucks it would probably be worth it to have them do it. It's not that the job is impossible it is just that if you are a person who doesn't typically tackle jobs like this you might find this a little bit difficult and messy. For those adventurous folks who don't mind a challenge then by all means, give it a shot!