Hey all, a week ago I was driving at 60 mph, then there was a big BOOM and massive vibration. I get home and check everything and it all seemed normal. So today I put it in reverse and back up about 10 feet where it makes a clunk and squeal kind of noise. I've checked the ujoints which are good. Driveshaft has some slop but I didn't think it would be a problem. I know the slip yoke needs grease but that shouldn't cause anything like this.
so I'm stuck. No ideas whatsoever. I wouldn't even know what to say to a shop to get it fixed as i don't know what's wrong lmao. Any suggestions would be great thanks

2004 excursion v10

 

How's your transfer case look?

 

Sounds like the inner needle bearing where the front axle stubs ride inside the wheel bearing. Reach around back of each front tire and try to spin the axle stub by hand. It should be hard to get moving, but once moving, be nice and smooth.