My rear window goes up and down pretty hard. The truck came with a crank gate but it was rusted out so I replace ti with an electric one when I restored the body. It has always worked slow, I got another motor from a junkyard thinking mine was worn and weak but it didn't help much. I put in a new battery and it worked a little better but not much. Every couple weeks it gets stuck at some point in the up down process and I have to take it apart and lube it up. The scissor arms seem to rub against the window slide parts and bind up over time. I just spray some white lithium on there and run it up and down with a cordless drill and go for a couple weeks. Anyone know if this is a common problem? any suggestions?