Growling from front passenger hub

[Ajax MD]

I might have some growling from the front passenger hub. It's difficult to hear over the engine.

This is an old, M998 with 7k axles. When I bought the truck, I got into the hubs and verified that all of the spindle nuts were tight and lock washers firmly engaged and tabs peened down. I broke down and greased the CV joints in the axles and put new boots on.

What is the common failure mode of a hub assuming the spindle nut hasn't come loose? Is it a bearing or are the reduction gears failing? The manual discusses total hub replacement but not much about replacing the bearings or gears. How can I determine exactly what in the hub might be failing?

 

[Mogman]

The first thing I would do is remove the magnetic drain plug and spread the stuff stuck to the magnet on a clean white piece of cloth, let the oil soak in and see what is left. that will tell you if your suspicion is correct, if it is then disassembly will be needed to determine the failure.
Most common is a bearing failure.

 

[Ajax MD]

Thanks, I'll do that. I'm not even certain that I have a problem. I just thought I heard a noise.
I found a pretty good hour long video of a complete hub reassembly. It requires some tools that I don't have, such as a travel indicator, dial indicator.

 

[Mogman]

A fine metallic mud is OK, flakes or chunks not good.

 

[Valley Rock]

Maybe Jack it up and start turning things to see exactly where the noise is coming from, it's more than likely just a wolverine or a honey badger stuck in your wheel .