Sorry to leave you all hanging.... Yup Minimans mostly has it! I surmised that while in 3rd, with the jam-nut backed off, the set screw holding the shift fork onto the rod finally wobbled out enough so that a 'downshift' to second occurred without moving the 3rd/4th fork (thus leaving it in 3rd), so as soon as the clutch was let out in second, the locked up box and the car's momentum broke the U-joints (yes the GCD101 type). When the axles were re-installed, the shifter seemed to "click" into all the gears but the box was actually in 3rd all the time (so could be "driven in 3rd or 4th" ... actually only third, but the shifter would click into both positions, so the customer assumed both) - So when 1st, 2nd, or reverse were selected too, no amount of engine would drive the car in two gears at once!
I talked to the customer and that's exactly what happened. I told him what to look for, and they got it all apart and found the little screw and it's jam-nut backed out of the 3rd/4th fork, and luckily, no other damage!
Sales & Technical Support at MiniMania
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