Bedroom slide out?

Mine squealed a lot too so I checked under the bed and found one of the little Plastic (?) slides was coming apart, so I replaced it. I also used some paraffin, yes good old paraffin like we used to rub on our sled runners, and lubed it good. I then went out and looked under the slide and saw that there were rub marks on the underside and rubbed those areas with the wax and ran it in and out several times waxing it each time. Amazing ,but the squeal stopped. I have also used that old engine belt lube that comes in a little tube. I have used that stuff on the belts of every vehicle I have owned and it does increase the life of the belts.