Product Description
Vehicles with GM 8L45 and 8L90 transmissions may exhibit high line pressure that results in harsh shifts, loss of cooler and lube flow and overheating of the transmission and converter. These problems may be caused by continuous oscillation of the shuttle valve within the shuttle sleeve, creating excessive wear and a path for balance line pressure at the pressure regulator valve to exhaust. This prevents proper positioning of the pressure regulator valve and can keep it in the higher pressure position. When in this position, bypass of excess pressure is not allowed and converter/lube/cooler feed pressure is greatly reduced.
Sonnax drop-in shuttle valve kit 154740-09K has upgraded materials and minimal clearances to prevent wear and restore proper hydraulic control. The length of the critical shuttle valve diameter has also been lengthened to provide better sealing and durability of the assembly.
- Shuttle sleeve is manufactured from highly wear-resistant billet aluminum to prevent wear
- Hardcoat anodized aluminum valve combats premature wear
- Critical valve spool made 30% longer than OE for added sealing and durability
- Drop-in Zip Valve™ parts install quickly and easily
Contents
- Valve
- Sleeve
Symptoms
- High line pressure
- Harsh shifts
- Low cooler flow
- Loss of lube oil
- Overheated transmission & converter
Cause
Wear of the OE pressure regulator shuttle valve sleeve due to continuous movement of the shuttle valve prevents proper line pressure control.
Correction
Install the drop-in Sonnax shuttle valve assembly with upgraded materials and increased critical valve-to-sleeve sealing engagement to restore hydraulic integrity and prevent future wear.
