It's an FX4, I can get underneath it. From what I have read on F150 forums, it's the slip yoke from what other guys are describing. Apparently I will crawl underneath it and put it apart to grease it. It's just irratating as heck from a dead stop, clunk when I get on the gas.
Thanks for the help
R.I.P. Mike "pappy" "broken rod" Green born 07-16-62 on to better fishing 06-10-08.