November 14, 2016
Governor oil leaving the solenoid reacts on the 1-2 and 2-3 bore plugs, which sequentially stroke the shift valves. These bore plugs stroke relative to an opposing spring and variable throttle pressure. Bore wear creates a loss of governor pressure, which affects shift timing. Due to this wear, shift timing changes with operating temperature and often causes a shuttle or late shift. When this leak is combined with a governor solenoid and transducer feedback, they are often too slow to compensate for this oil loss. The throttle circuit is also prone to wear and has TV pressure variation from cross leaks, which then affect shift timing. These cross leaks often come from the 1-2 accumulator piston seals, throttle control valve, TV checkball and/or a distorted valve body.
Sonnax valve body layouts provide a detailed overview of individual units making it quick and easy to determine what’s available for the specific valve body you’re working on. See all Sonnax valve body layouts.