My only other suggestion would be to make sure the valve operated by the dump pedal is closed when the pedal is released. A collapsed gearbox mounting rubber can cause the linkage to tighten up, as could a bent link rod to the gearbox. Otherwise I suggest a more professional appraisal as it could be a problem in the gearbox/torque convertor. Lets hope not, look at the easy bits first!
Mr. Toad
May 2009
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