Ok...you guys have ALWAYS come thru with the correct answer, so here goes (i apologize for the long post). 2002 Ford F250 4x4 Superduty Lariat (4 door). Just changed the locking hubs to a new set of Warn manuals. I began to periodically hear what sounds like a rumbling/bearingish/howling kinda sound. Happens when you hit a bump at any speed...then howls till you hit another bump..goes away..then process repeats. Come to a complete stop, and the sound usually goes away till you hit another bump. The hubs are "free" at this time. Heres the weird thing...when the noise starts...I switch it into 4 wheel drive on the dash...the sound instantly goes away. Click it back outta 4 wheel drive (hubs are still unlocked this whole time) and the sound is gone. drive some more down the road, maybe hit a slight bump, and the sound returns. Switch it back into 4x4...sound instantly goes away. Its not really in 4 wheel drive, cause the hubs arent locked in...but that cures it till I take it back out. Any ideas as to what could be causing this howling ? Its getting worse, and you can feel a slight vibration in the floor now when its doing it. Thanks guys.

 

Your hubs are not unlocking. You will get some vibration from the front axle if you are not powering it. (hubs locked, not in 4wd).

I curious what happens when you lock them in, and don't turn the switch to 4wd. If there is no difference, you have a hub problem.....

 

I did some more searching...and found threads with EXACTLY the same problem I'm having. So far, the culprit seems to be dry/worn out/bad needle bearings at the end of the front axle shaft. I'm gonna pull it apart tomorrow.

 

Yup needle bearings. Just went threw it on mine. I replaced the hub bearing assy because it was under warrenty but it galled up the stub shaft so that got replaced and a new u-joint and both seals. The torrington needle bearings are only about 13 bucks here and easy to change but my assembly was under warrenty so I just got a new one. I would suggest locking in the hubs till you get it done or your stub shaft will probably be galled.

 

But it may not be the replacable needle bearings. It might be the set thats inside the hub assembly itself and those unfortunatly are not replacable as the hub assembly doenst come apart. But if it is the one that can be replaced, you will have to check the axle stub for damage as well.

 

Well...took it apart this morning....and it was the needle bearing at the end of the shaft. It didnt tear up the shaft (whew), and as soon as I had the hub off...4 of the needle bearings fell out...lol. I went to NAPA, and $11 later, had it repaired. Thanks for the help guys !!!!!

 

Do you uave the part number for the needle bearings you changed in the front hub.

 

I believe it is B1009

 

The part number was B2110. Thanks