I don't think the clutch is the reason it wouldn't work on a turbo motor... I think it's the MASSIVE amount of heat the motor produces pushing the taller diff.

LV is pretty flat too, so the 240 cruising at 60 on flat ground likely has little heat produced.
the reason you had no heat was the WP was not turning much if any at all.
actually, I think the wp would be turning backwards without the motor. the heat likely was moving thermally, not the wp pushing it.

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!