September 30, 2005
Anatomy of a Transmission: Oil Flow in the Pump-PR-Converter-Cooler Lube Circuits
Gregg Nader
Symptoms:
- Soft shifts
- Low line pressure
- Harsh shifts
- High line pressure in Reverse
- Clutch & band failures
- Low converter pressure
- High line pressure
Cause:
Continuous oscillation of the pressure regulator valve causes valve body bore wear, which results in line pressure irregularities and valve instability. Severe wear of the boost valve sleeve allows EPC and reverse oil leakage.Correction:
Sonnax oversized pressure regulator valve and boost valve kit allows the valve body bore to be restored to normal operating condition.U151E, U151F, U250E
Oversized Pressure Regulator & Boost Valve Kit
Part No. 27741-08K
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Tooling:
- 57917E-TL8
You need this if... View Instructions Find a Distributor
Toyota/Lexus vehicles with U151E, U151F and U250E transmissions may exhibit insufficient line rise in the drive ranges, excessively high pressures in Reverse and shift issues. This may be caused by continuous oscillation of the pressure regulator valve and boost valves causing severe wear.
Sonnax oversized pressure regulator and boost valve kit 27741-08K features upgraded materials and extremely tight tolerances to restore and maintain proper hydraulic control.
- Hardcoat anodized aluminum valves combat premature wear
- New spring is included to work with the oversized valve and re-establish OE regulated pressure specifications
- Kit includes an increased ratio boost valve assembly specially designed to work with the oversized regulator valve
- Pressure Regulator Valve
- Pressure Regulator Spring
- Boost Valve
- Boost Sleeve
- Boost Valve Plug
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.
Toyota/Lexus U151E/F, U250E Valve Body Layout
January 21, 2013
