Vehicles equipped with ZF8HP45, ZF8HP55 and ZF8HP70 transmissions often develop erratic or high line pressure due to excessive wear in the OE pressure regulator valve bore and/or sleeve. This wear allows critical oil loss, preventing proper line pressure regulation. Without correct balance oil pressure, the PR valve will be out of its desired position, resulting in line pressure instability and possibly restricting cooler and lube flow. A deteriorated bore can cause lowered line pressure, resulting in soft shifting and burnt clutches. Reconditioning the bore and installing Sonnax oversized pressure regulator valve kit 35740-01K renews pressure regulator action for revived line pressure control in all ranges.
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.
October 17, 2016
Topics: Transmission Report Newsletters Transmission ZF ZF8HP70 Transmission ZF8HP45 TransmissionRead Now
December 07, 2016
Topics: Vacuum Test Guides Vacuum Testing Transmission ZF ZF8HP70 Transmission ZF8HP45 TransmissionRead Now
August 11, 2016
Topics: Webinars Transmission ZF ZF8HP70 Transmission ZF8HP55 Transmission ZF8HP45 TransmissionWatch Now
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.