This is the reply I received back form Dave Ashcroft about the MT82.
Hi Rick,
Ford / Getrag don’t release any figures for the torque capacity of the MT82 but it would appear similar to the R380,
As you mention we upgrade 2 of the bearings that often fail on the R380 and although we are starting to see a pattern on MT82 failures we don’t have any upgrade options as yet, one common failure is the needle roller bearing that goes between the pinion and mainshaft, not easy to upgrade as you are restricted by the pinion wall thickness.
Having said that I think they would still give a good lifespan and no worse than an R380, in the UK its common to tune these to 450Nm and they still last OK,
Regards
Dave Ashcroft