How to Inspect U Joints

Video Transcript

"In this clip we are going to talk about the proper service procedure for removing and replacing a rear axle U joint on a Ford Explorer. In this step we are going to talk about the drive shaft and inspection of your U joints. The drive shaft is the piece that transmits the power from the transmission to the wheels. Now being that your suspension moves up and down as you go down the road they have to make these joints flexible so as the drive line angle changes the shaft won't snap out. This U joint up here in the front by the trans is good. They generally are. They generally last twice as long as the rear. I'm going to show you the motion of it, how it's really nice and smooth, both left and right and up and down. That's a good U joint. You don't see any cracks or mechanical damage in it. All the clips are present. As you can see all the retaining clips are there. I'm going to turn my drive shaft around for you and show you my bad U joint. What we have here as you can see it looks good this way, however the left and right direction I couldn't turn if I had to. It's actually beginning to develop a little bit of play between the U joint and the cuffs if you look real close you can see it. That right there. Those cuffs are slopping around on the U joint and not actually turning. What has happened is the seals have failed, water intrusion has gotten inside the cuffs and caused them to corrode and seize together. That is the proper way to inspect your drive shaft and determine which U joint is bad."