Bearing or Manual Hub?

[Ian1976]

Hello All! Long time reader, new poster..

2000 F250 SD Lariat, 7.3L, 140k

Story goes like this. When in motion, and then applying brakes, a loud snap (or clack, but only one) noise is heard and felt from underneath the truck, presumably the front driver side. Jacked it up, and found out the UJoint was literally trashed.

Ok..new UJoint, put back together. Noise still remains. Jacked back up again, and notice when I spin the tire, it takes maybe 4-6 inches of movement before the half-shaft spins.

Now, on to the Locking Hubs. The outter portions of the hubs are trashed. Couple winters ago in Iowa, so cold the outter "knobs" shattered off of both hubs when trying to manually lock them.

So the questions: Is this the bearing going bad? Or the locking hubs bad (or halfway engaged)? I don't really understand the locking hubs, tried to pull them out but think they are seized in at the moment.

If I missed anything, please let me know. Need to get this beast back up, but don't have the money flow at the moment to replace everything (always about money!).

Appreciate everything!

[klhansen]

Welcome to TheDieselStop

If the locking hubs can't be operated anymore they'll likely need to be replaced.

Was it the axle or driveshaft u-joint that you replaced?

You should be able to diagnose wheel bearings, ball joints, etc. by jacking up each front wheel and checking for movement. If the wheel bearings are shot, you'll see movement between the brake disk and steering knuckle when you grab the tire and move it in and out top and bottom (rock the tire sideways.) To check the ball joints by sticking a prybar between the tire tread and ground and pry up, looking for movement between the steering knuckle and the axle housing.

Check the locking hubs by locking them and turning each wheel and observing whether the axle turns with the wheel. You can also do that wht the wheels on the ground by reaching around and grabbing hold of the axle u-joint and trying to turn the axle. With the hubs locked you should get only a couple of degrees of rotation of the axle.

As far as getting the locking hubs off, pull the snap ring off, then smack them with a 2x4 on the side, then turn the wheel and smack again. They should eventually loosen up.

There's a needle bearing inside the wheel bearing assembly that suppports the axle shaft as it goes into the knuckle. If that wears out, when in 2WD, the axle can "walk" around inside the rotatiing bearing hub and make a noise like the rumble strip on the road. If the noise goes away when the hubs are locked, that pretty much confirms the axle bearing are bad.

[444-4D]

My first guess is a loose ,worn out, lower ball joint.