Sometimes my power windows won't come down unless I hold the window switch down and slam the door shut. Is there anything that I can put on the door seal where the window goes into so the window can come down?

 

You can use a silicone spray lube on the guides. More commonly the motor is headed south. You can try disassembling and cleaning the motor brush area, replacing the motor or replacing the regulator assembly - the whole shabang.

 

I had the same issue in my 1500 and $21 replace the switch assembly from Amazon and 2 minutes had it in and fixed.