TOY: noises from rear axle

[Roger Brown <rogerb@xxxxxxxxxxxxxxxxxx>]

> About a week ago a squeeling noise started from what sounds like the
> rear axle, rear drive shaft area.  The noise was only noticeable when
> coasting in a low gear, first or second.  Noise got louder and did it
> under power.  I noticed some oil leaking from the diff near the drive
> shaft flange.  So I drained the diff and  put some new 80w-90 gear oil
> in.  The noise stopped for a day or two. It came back today.  The noise
> is now much more noticeable when in low gear and under power, the noise
> almost isn't there when coasting in gear.  I lubed the drive shaft and
> changed the gear oil again.  Neither changed the problem.  The fluid
> that came out of the diff seemed dirty, lots of flecks of metal.  The
> magnetic drain plug had lots of metal pieces sticking to it.  If it is a
> bearing or other part in the rear diff, would it be best for me to go
> find a junk yard diff?  I do need to regear the axles, but am running
> low on cash.  I also have 3" longer than stock shackles with stock

I vote for a bad pinion seal and probably pinion bearing.  Did you check and
correct the pinion angle on the driveshaft after installing the 3" longer
shackles?  If not, you probably have a bad angle at the bottom which caused
vibrations that led to the pinion failure.  

http://reality.sgi.com/rogerb/4x4/CheapTricks/Driveline-101.html#FixingProblems