Severe wear of the TCC regulator valve bore caused by oscillation of the OE valve allows regulated secondary line and TCC signal pressure to leak to exhaust in listed Ford and GM 10-speed transmissions. This wear minimizes secondary line pressure control resulting in overheated fluid, loss of converter feed pressure, TCC release concerns, TCC slip code concerns and potential transmission control module (TCM) errors.
Installing drop-in Sonnax TCC priority valve kit 105740-03K eliminates the leakage of secondary line pressure by creating a new conditioned bore area for the upgraded valve to operate in. The O-ringed end plug provides a positive seal and prevents critical TCC signal fluid from leaking to exhaust. Both of these Sonnax features restore normal TCC operation by restablishing the hydraulic integrity of this circuit.
Vacuum testing at the port(s) indicated fails to hold the recommended minimum in-Hg, or if wear is visually detected.