Pretty sure I have bad news.
This sounds like classic worn stub axles.
Briefly, there was a mismatch between the stub axle O.D. and the bearing's I.D. This allowed some wobble in the assembly. Over time, the softer stub axle gets worn down by the harder bearing inner race.
Fix?
Spray weld the axles and re-machine.
Or, much easier, buy new stub axles. Wilkinson now offers a set, with nuts, for about $400.
You can also easily upgrade to a double-wide inner bearing at the same time. Wilkinson sells them with the shortened spacer you will need.
OOOPS - your GT5 may have the double wides already, if a true GT5. Not too sure on that, though.
The tool can be bought from any vendor for about $100, or from IPSCO for about $70:
http://www.ipsco.org/Pantera%2...s/AXLE%20SCOKETS.htm
To answer you question, the torque for the nut is about 400 foot pounds. Do not use red loctite!
Larry
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