Symptoms:

  • Harsh shifts
  • Neutral shifts
  • Gear loss
  • Delayed engagement
  • Wrong gear starts
  • Flare shifts
  • Gear ratio & solenoid codes

Cause:

Bore wear at the priming valve allows pressure escape that causes drivability problems.

Correction:

Stop pressure loss and restore normal solenoid feed pressures by installing the Sonnax drop-in priming valve and seal kit

845RE, ZF8HP45, ZF8HP55, ZF8HP70

Priming Valve & Seal Kit
Part No. 35740-37K

ZF valve name: DR-RED-V (DR-V) Chrysler valve name: PR-V

You need this if... View Instructions Find a Distributor

In Chrysler 845RE and ZF8HP45/55/70 units, the variable force solenoids control clutch apply/release, torque converter clutch apply/release and line pressure. The priming valve ensures proper flow and pressure to the solenoids, which is especially crucial during hot conditions and low pressure. Low solenoid feed pressure at idle can create delayed engagement or wrong gear starts. This priming valve also limits the maximum pressure to all the solenoids. Excessive solenoid feed pressure can flood the solenoids causing gear ratio codes, harsh up/downshifts and excessive line pressure.

Installing Sonnax priming valve and seal kit 35740-37K eliminates bore wear and stops leakage for proper solenoid pressure control by incorporating a seal at the critical valve spool associated with bore wear.

  • Hardcoat anodized valve combats premature wear
  • Scarf-cut seal on critical valve spool expands to prevent leakage passed any wear
  • O-ringed end plug seals critical oil circuit against wear
  • Drop-in Zip Valve parts install quickly and easily
Learn More About Zip Valve™ Drop-In Repairs
  • Valve
  • Seal Scarf-cut
  • End Plug
  • O-Rings (2)

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.

ZF8HP55 Valve Body Layout

ZF8HP55 Valve Body Layout

ZF8HP45/70 Valve Body Layout

ZF8HP45/70 Valve Body Layout
  • 845RE, ZF8HP45, ZF8HP55, ZF8HP70 Priming Valve & Seal Kit 35740-37K
  • 845RE, ZF8HP45, ZF8HP55, ZF8HP70 Priming Valve & Seal Kit 35740-37K

You need this if...

Vacuum testing at the port(s) indicated fails to hold the recommended minimum in-Hg, or if wear is visually detected.

845RE, ZF8HP45, ZF8HP55, ZF8HP70 Priming Valve & Seal Kit Vacuum Test Locations