1/99 F250SD destroys hub assemblies

[maddawg89]

Hi, I got my truck back in April and one week later the passenger side front hub assembly welded tight! So, I replaced it. Then, back in September, the driver side hub assembly disintegrated. I replaced it. Now, just four months later, it's making a horrible grinding noise and vibrating just as it did before it went out last time. AutoZone is shipping me a new one. Any ideas as to why its killing the hubs? My tires are not overly huge, the rims are 16x13 according to the tire stores caliper and the tires are 305/70/16's. they are not putting too much strain on the hubs being wide are they? Any ideas?

[NoRalPh]

Try Locking the Hubs IN (doesn't have to be in 4WD, just so both ft axles are turning with the tires) and see if that noise goes away. The hub bearings might actually be fine but the needle brgs are failing because your stub axle is "chewed-up" where they ride...

[maddawg89]

Well, I'm bummed and I'm relieved at the same time. I have manual locking hubs, but it appears my truck at one time had auto lockers. There are vacuum hoses running to it on both sides. So when I pulled the hub off, my spindle was flopping around really bad. The entire vacuum seal/bearing had disintegrated! So I'm guessing that was the problem of the grinding noise and the reason this will be the second hub in 4 months. The hub is under warranty and the seal is about 52 bucks. I have to wait till Tuesday to get the part.

[NoRalPh]

Yea but, that spindle (stub axle?) will flop around quite a bit without the hub...

There's nothing wrong with Manual Hubs, Many people get rid of the vacuum hubs because of leaks and just go with manuals. And that seal (called a Knuckle Seal) isn't supposed to support the stub axle at All!

What does the area of the stub axle, that those needle brgs ride-on, look like?

Did you ever try driving it with the hubs Locked to see if the noise went away?

[maddawg89]

Well, see, last time a replaced the hub, i didnt get the lock ring in right on the locking hub and it came off going down the road, so Ive been without 4x4 for a bit....

When I pulled the hub of, that bearing/seal whatever it is was in three pieces and all the rollers were either ground to powder or rolling arond loose between the hub and the bearing. I could move the spindle around way too much. Move than what it should normally be. The spindle itself, where it sets in the bearing, has three grooves worn in it... I will be replacing it. Pretty quick.

I'll take a picture tomorrow and post it.

Got my hub today. Just have to wait till Tuesday when I can cash my check to buy that bearing. Im a broke college student....