How to repair a drip on the windshield

For several years, the only acceptable way to repair a water drip on the windshield was to remove it completely and reinstall the glass. The concern was the potential development of rust in all the windshield frame, especially in view of the front part and rear glass are the structural components of the cover and add rigidity to an area that is otherwise weak.

It was later discovered that water leaks are the result of poor adhesion between glass and urethane, not the urethane to the structure. Consequently, in the early 1990s, General Motors issued a Technical Service Bulletin recommending that water leaks be repaired from inside the car.


  1. Sit inside the car and carefully fold back the roof liner into the general area where the water is leaking. Tell an assistant to pour water slowly over the windshield.
  2. Light up with a flashlight over the area where the water begins to drip. Grab the drops of water with a towel and continue to watch until the water stops. Dry the area well.
  3. Apply a small amount of silicone sealant to the exact spot where the water is dripping. Use just enough to cover the area. Press the silicone into the hole with a sweeping motion. Clean the area several times and apply a small amount of sealant. Do not apply an excessive amount of sealant.
  4. Test the repair after allowing the sealant to dry for two hours. Use a flashlight to check that the dripping has been repaired by telling the attendant to pour water over the windshield.

Tips & Warnings

  • This is a very reliable and permanent repair.
  • Leaks that occur after a windshield has been replaced are of unknown origin and the windshield should be removed and re-sealed.