Axle bearing noise

I've been noticing a whine getting louder and louder over the past few thousand miles, and wondered what the hell it is... Can you help? It's an open 8.25 axle, on a 93 Sport.

It appears to be related to speed, and only appears under load when the diff has warmed up. I'm assuming it's the bearings in the diff, as I changed the axle bearings when I converted to rear discs.

How can I tell if the noise is the pinion bearings, and what will have to be done to get it fixed? Am I looking at sending it to a transmission specialist or can it be done with normal tools at home?

Thanks.

If the noise occurs with the frequency of the wheelspeed (which you can easily check by slapping some packing tape on the drivers front tire, then driving around and comparing the ticking from the tape with the woo-ing of the bearing) it's either a wheelbearing or carrier bearing. Both of those can be changed without too much difficulty, though the carrier bearing will require some ingenuity or a trip to the machine shop to press a new bearing on.

If it's a pinion bearing, the noise should occur roughly 4 times as frequently as wheelspeed. That it only happens under load points to pinion bearing as well.

Here's a couple links I had saved after searching on the subject

http://www.naxja.org/forum/showthread.php?t=77904&highlight=pinion+bearing
http://www.pirate4x4.com/articles/tech/billavista/Gear_Setup
http://www.dippy.org/svcman/sm03a.html#REARAXLEASSEMBLY
http://www.naxja.org/forum/showthread.php?t=24710&highlight=howl
http://www.naxja.org/forum/showthread.php?t=62600&highlight=pinion+bearing
http://www.naxja.org/forum/showthread.php?t=68760&highlight=howl
http://www.naxja.org/forum/showthread.php?t=46727&highlight=carrier+bearing
http://www.naxja.org/forum/showthread.php?t=39383&highlight=pinion+bearing
http://www.naxja.org/forum/showthread.php?t=68760&highlight=howl
http://www.jeepforum.com/forum/showthread.php?t=109859
http://www.jeepforum.com/forum/showthread.php?t=279513&highlight="carrier+bearing"

Thanks for that - great sources of information. And balanced too!

I really need to work on my logical searches - I didn't get half of that...