Cause:
All solenoids are fed by the solenoid regulator valve. Worn valve/bore surfaces allow critical pressurized oil to cross leak to the sump, reducing available oil pressure and volume for the solenoids. Shift quality will be adversely affected by wear and operating temperatures.
Correction:
This Sonnax kit eliminates cross leaks and loss of critical oil to the sump, restoring correct oil pressure and volume available to the solenoids.
In ZF6HP21/28/34 (Generation 2) units, the variable force solenoids control clutch apply/release, torque converter clutch apply/release and line pressure. The solenoid pressure regulator valve insures proper flow volume and pressure to the solenoids during hot conditions and low pressure operation. Low feed pressure at idle can create delayed engagement or wrong gear starts. This valve also limits the maximum pressure to all the solenoids. Excessive solenoid feed pressure can flood the solenoids causing gear ratio codes, harsh up/down shifts and excessive line pressure. The Sonnax oversized solenoid pressure regulator valve kit restores proper solenoid function.
Kit fits either M-shift or E-shift valve bodies
Valve is hardcoat anodized to reduce wear
Matching spring reproduces OE function with the oversized valve
Note:
Kit is NOT compatible with ZF6HP19/26/32 (Gen.1) units.
ZF valve name: DR.REO-V. Tool Required.
Symptoms:
Cause:
All solenoids are fed by the solenoid regulator valve. Worn valve/bore surfaces allow critical pressurized oil to cross leak to the sump, reducing available oil pressure and volume for the solenoids. Shift quality will be adversely affected by wear and operating temperatures.
Correction:
This Sonnax kit eliminates cross leaks and loss of critical oil to the sump, restoring correct oil pressure and volume available to the solenoids.
In ZF6HP21/28/34 (Generation 2) units, the variable force solenoids control clutch apply/release, torque converter clutch apply/release and line pressure. The solenoid pressure regulator valve insures proper flow volume and pressure to the solenoids during hot conditions and low pressure operation. Low feed pressure at idle can create delayed engagement or wrong gear starts. This valve also limits the maximum pressure to all the solenoids. Excessive solenoid feed pressure can flood the solenoids causing gear ratio codes, harsh up/down shifts and excessive line pressure. The Sonnax oversized solenoid pressure regulator valve kit restores proper solenoid function.
Note:
Kit is NOT compatible with ZF6HP19/26/32 (Gen.1) units.
Contents:
SONNAX Installation Instructions