I had posted several times about the rear wheels locking up on
accelerated reverse with no response from anyone.
Your sheared CVs may be a related matter.  When the gears lockup
the inertia from the movement creates a strain on the CVs and
eventually the axles get sheared. This is just a hypothesis.
Your lockup may be so slight that you may not feel or notice it.
It is similar to trying to drive the vehicle with binding
brakes. The engine torque is twistng the axle which is
experiencing heavier than normal load.
Anyone care to comment ?

Terry

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