Wear in the forward and reverse regulating bore and on the major spool areas of the regulating valve is common in the Subaru TR580 continuous variable transmission (CVT). This wear minimizes clutch output pressure control resulting in forward clutch failure, delayed Forward and delayed Reverse.
Reconditioning the bore and installing Sonnax oversized forward and reverse regulating valve kit 823740-05K eliminates the leakage of solenoid pressure fluid to exhaust. The incorporation of annular grooves on the outboard and inboard major diameter spools of the valve ensures the valve functions and operates in the center of the bore. The O-ringed end plug provides a positive seal and prevents critical solenoid pressure fluid from leaking. Both of these Sonnax features ensures your unit will have proper clutch output pressure through all drive ranges.
Vacuum testing at the port(s) indicated fails to hold the recommended minimum in-Hg, or if wear is visually detected.