The door window is cranked up tight in the cloth channel and off you go on your daily errands. Suddenly, the glass begins to slowly lower as you drive over side roads or contact a rough surface. In comes cold air, rain, and wind! Even the window handle turns. What's this all about? Do you tape the window closed or wire the handle so it will not turn?
You have a window regulator spring problem! This large 2" diameter round spring has either broken or become disconnected.
With no spring tension on the regulator, the weight of the glass creates the lowering of the support arm and window. Sorry, there is no good fix other than removing the regulator from inside the door. The picture below shows this circular Clock spring. It must be large to hold the weight of the glass panel.
In the early 1960’s Jim Carter Truck Parts was visiting nearby Ron Manus Truck Parts. Ron is a “total” expert on 1967-72 Chevy/GMC trucks.
A customer drove in with this component. Ron quickly identified the problem. It was worthy of a tech article!
