Weak Electric Window Motors?

My son has a 1984 Chevy Blazer. The front electric windows raise and lower but are very slow. The tailgate window will lower slowly but will not raise. We had to disconnect the cable from the motor and turn it by hand to raise it. We checked the battery with a multi-meter. The battery at rest is 12.5V and is 14.5V when the engine is running. Is it a possibility that there is a voltage drop from the window master switch to the window motors? It seems strange that all of the window motors are weak. Any opinions are appreciated.



Port Vincent, LA

You will likely need new motors at that age, and all sliding parts need to be cleand, aligned and lubricated with a silicon lubricant.

Try cleaning and lubricating the window channels.