The driveshaft of the TH 350 will be turning several items inside the transmission, in particular, a one-way roller clutch that will create more drag when turned in one direction (don't remember which way offhand). There will also be at least one multi-disc clutch and a planetary gear set in motion. Disconnecting the driveshaft at the rear end pinion flange will reduce the drag considerably.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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