15,000+ Posts & Climbing
Join Date: Jun 2009
Location: Sault Ste Marie, Ontario
Re: Pulling a tractor with a hydrostatic transmission, bad?
If you pull a hydrostatic tractor without engaging the by-pass or shifting the two speed rear axle into neutral (if equiped), you in effect are trying to run the hydraulic system backwards and the oil tries to go the wrong way through the hydraulic motor and pumps which effectively become check valves stopping the flow. Net result is very high pressure in parts of the case designed for low or zero pressure. You are trying to turn the tires against a very high ratio reduction unit with a lock on the other end.
Comparable scenario in automotive terms, pull a manual shift four wheel drive truck with the transmission in bull low, the transfer case in four wheel drive, low range and a large V-8 engine.
Bottom line, hydro is ruined because the case is broke, and so are you when you buy the replacement.
Last edited by TUDOR; 09-06-2009 at 04:14 AM.