That procedure was actually part of what they called a “rock test” at Chrysler Chelsea Proving Grounds.
I don’t recall if it was at a WOT or just a high rpm. It was done to simulate getting stuck in snow, etc. I believe it had to handle 50 cycles of reverse to drive to reverse.
....boy they must have left that test in the past with the 94ish RH trans came along. We repaired so many of those that had gotten stuck. Seems to me most of them welded the output shaft to the OD piston retainer. I was just getting into “the business” at the time and a guy I worked with was losing a check ball and drilling the separator plate. Engaged a bit harsh... but they lived.
The intermediate shaft getting stuck in the OD piston retainer is due to lack of lube or extremely high fluid temperature. Likely failed lockup disc back in the early 90’s or snow plow use without the added cooler needed for same.
As for the rear band failures back then, that was Engineering listening to the Customer Advocate Group at the time, people were buying more and more trucks and complaining how they had harsh reverse engagements. So they used two holes - one small and one larger to apply the L/R band using a check ball to float between the two holes. Fine for the average driver but for snow plow use they killed the band. I worked on the Tech Line at the time and our fix was what your buddy was doing.
The two holes and ball slowed the rear band apply so guys doing plowing would toast the band because they didn’t come to a complete stop before placing in manual low or reverse.
The rock cycle wasn’t to test the band, but to test the ORC, as the vehicle actually never went anywhere, just engaged the gear then shifted to the other gear back and forth.
