[Rovernet] Diagnostic help please

[Scruggs Family]

In my 44 years of P6 ownership I've had three final drive failures and they
were all accompanied by an increasingly louder whining sound.  I've never
had one go 'thump.'  When I've had a thump it has been a failed half-shaft
U-joint... several of those.  For my experience when you get an OEM
replacement U-joint you get one that strangely doesn't have a zerk fitting
and cannot be lubricated... so you are left with whatever lubricant that may
or may not have been injected at their point of origin.  When replacing half
shaft U-joints I make a point of getting aftermarket units... the same, I
have been told, that early IRS Corvettes use... that do have zerk fittings
as they will last much longer with occasional lubrication.  

I am seriously considering replacing the U-joints in my half shafts with CV
joints as they do not have near the drag of a U-joint.  Hand push a P-6 and
then any other 3,000lb car... I contend the extra 'weight' of the P-6 is due
to U-joint drag/resistance.  May be costly to make the change but it will
amount to a horsepower increase with longer life.  And while you're in there
have an aluminum /aluminium driveshaft made as you will appreciate the
weight reduction of the rotating mass.  

When you pull the handbrake it ratchets the rear caliper pistons into the
pads to take up any slack.  If the cable or the ratcheting mechanism is out
of adjustment then the pads on that side will eventually not touch the rotor
before the other side does.  If your calipers are not leaking then they are
most likely victim of poor adjustment/maintenance which can be addressed
without dropping the differential.  Yes, it's tight up in there but for my
experience dropping the differential is one of the last things you want to
do unless you have a lift and three husky, amiable friends.  Also check the
top edge of the differential mount for stress cracks while you're under
there and weld or replace as you choose. And tighten the panhard rod
mounting hardware tighter than factory specs so it won't shudder under
cornering loads. 

Gross Scruggs
Annapolis MD