Wear is commonly found at different areas in the ZF5HP24 pressure regulator valve bore. Wear at the inner portion of the bore causes high pressure spikes leading to broken drums, pistons or other parts, as well as restricting converter/lubrication flow. Wear at the spring end of the bore allows line pressure to exhaust resulting in low line pressure, soft shifts and burnt clutches. The Sonnax oversized pressure regulator valve kit 139740-01K restores valve-to-bore clearances so the pressure regulator valve can maintain correct pressures.
Contact a Sonnax Parts Distributor.
Vacuum testing at the port(s) indicated fails to hold the recommended minimum in-Hg, or if wear is visually detected.