I have a 94 F150 4x4. It has automatic hubs on it. i jacked it up to see if the driveshaft from the transfer case was turning and i was so i was relieved that the transfer case is all good, but i looked up by both driveshafts that come from the front differential. The right one was spinning but the wheel would'nt turn. The left driveshaft wasn't turning so I don't know what's going on. I don't know if both hubs are bad or is there something wrong with the front differential? Would appreciate any help on this.

 

Assuming you mean you got all 4 wheels off the ground, engine running, transmission in drive and transfer case in 4x4, so the auto hubs should lock in. Your front differential is open, so the power will take the path of least resistance. It sounds like the right hub is failing to lock. I would start the inspection there.

 

It sounds like at the least the hub is shot, worst case the axle shaft. That is if the hub was engaged.

With the hub engaged and the front end off of the ground, grab the axle half shaft and spin the wheel. They should be "locked" together, if not then the issue is in the hub.

The front diff is an open diff, no posi or locker, so only 1 wheel drives the truck so it can make turns. If you hold the wheel that spins with the drive shaft and turn the drive shaft then the other wheel should spin. If not then the issue is probably inside the diff it self.

Good luck.

 

Thank you I appreciate it.

 

A couple years ago I had an issue with my 4x4 system and it ended up being a disconnected/torn vacuum line going to my left hub. I have an '06 so your setup may be different but it's something worth looking into since it's a $5 fix.