Just did this operation. As all moving parts, the window mechanism needs lubrication. I have made better experience with white lithium grease spray or PTFE Spray. Its more durable and stays better in place than silicone spray and lubes like hell. Use the silicone spray on the sides of the gasket of the glass. I clean and relube all moving parts after 2 years. Never had to replace any moving part due to failure.