Folks, I had the clunk on my 97 f150 and had some leaf spring work a while back. Still clunking so I took it to a drive line shop and they pulled off the drive shaft and lubed, with lithum grease the slip yoke. Clunk gone. That was 8 months ago and now it's back. The first time they told me there was some minor wear of the slip yoke and greased it up. My question is did Ford redesign the slip yoke, cause if they did I'm going to replace it, if not then i'm just going to get it lubed again.

Thanks for the Input...

 

Ford uses teflon grease on the slip yoke (P/N:: D2AZ-19590-A), not lithium. It should last longer than lithium.