Front end noise after hitting a bump

[Chewman]

Today my Ex started to make a terrible sound from the front left wheel area. I hit a good pot hole. Hey it's Michigan Roads! The Ex made this horrible sound like splines not enguaging. Not a gear grind. More of a loud medium pitched whir. Now it will do this when ever I hit a bump. I can clear it if I stop and sometimes it will clear itself before I get stopped.

It wont make the sound if in 4X4.

The only 2 things I can think of are:

1) The bearings are gone after 180K miles and it's cocking when I hit bumps.

or

2) something is causing the axle to cock in the hub and I am hearing the splines rubbing on something. The axle feels tight.

Anyone else experience this or fix this? What was it?

I'd hate to shelll out the money for a new hub assembly and hav eit not be the problem.

 

[Zookie400]

chewman - replied to your pm. it sounds just like the truck i found the bearings loose on.

 

[Tail_Gunner]

....It wont make the sound if in 4X4....

That is a real good clue that the outer axle shaft bearing (not the hub bearing) may be shot.

In the wheel bearing hub assy, there is a caged roller bearing that supports the outer axle shaft when the lockout hubs are unlocked. In 2wd, the outer axle shaft is stationary. The hub bearing spins around it with the axle shaft bearing spinning and supporting the outer end of the stationary axle shaft. Therefore, a bad outer axle shaft bearing will make sound as it spins.

When 4wd is engaged, the outer axle shaft is engaged to the lockout hub and spins with the wheel. Since there is no difference in relative motion the axle shaft bearing is not spinning. Since there is no difference in relative motion, a bad outer axle shaft bearing makes no noise.

The good news is the outer axle shaft bearing is replacable.

I hope this all isn't too confusing.

 

[JLDickmon]

I agree, but I'm pretty sure those are hub units in the X..
hope your credit card has some room on it, them suckers are non-serviceable AND expensive.

It's not a bad job to do yourself, just remember to get a new stud kit with the bearing.

Jack the front end off the ground and spin each wheel in "free" while holding the spring.
The bad side will be the one you feel the vibrations in.

 

[Chewman]

Thanks guys fore all the fast advice!

I know what I am looking at after work tonight!