1992 Ford 345D loader slipping in high range but ok in low range

[Doc Russ Miller]

This has started recently. Placing the machine in high range it will not move till I raise the rpm above 1500. However in low range everything works just fine.
Puzzled. looking for clues.

TYIA

 

[Check Break]

I take it you have the 8spd transmission behind a torque converter. One cause could be the beginning of converter failure. It would be a good idea to prove out the converter in low range by pushing or pulling a load. Is it really ok or not. You're describing a high stall situation which is higher than it is normally. Your converter may not be delivering the torque to the shuttle that it once did.

Clutch pack in the shuttle could be slipping. Perform a pressure check.

Your park brake could be set or hung up.

That will get you started. If none of the above, check back.

 

[Doc Russ Miller]

thank you, where would I check the pressure or the convertor.