Product Description
5L40E 5L50E Pump Boost Valve Kit
OE RATIO WITH .474'' & .441'' DIAMATER VALVE SPOOLS
Sonnax Part Number: 55209-04K
NO TOOLING REQUIRED
Vehicles with GM 5L40-E and 5L50-E transmissions are prone to poor line rise or high Reverse pressure problems causing poor shift quality and clutch failure due to leakage at the boost valve assembly. Sonnax offers two boost valve kits: the 55209-01K performance ratio (higher line rise and firmer shifts) and the OE ratio 55209-04K for factory performance.
- Hardcoat anodized aluminum valves combat premature wear
- Boost sleeves are made from alloy aluminum specifically designed to resist wear
- Increased performance ratio 55209-01K or OE ratio 55209-04K assemblies are available
- Drop-in Zip Valve™ parts install quickly and easily
PACKAGE CONTAINS
- Valve
- Sleeve
- O-Ring
SYMPTOMS
- High line pressure in Reverse
- Low line rise
- Gear ratio codes
- TCC slip
- Flare shifts
CAUSE
The boost sleeve increases line pressure for shift quality, engagement and proper TCC apply. As the sleeve wears, torque signal oil will leak to exhaust and line pressure will not increase as commanded.
CORRECTION
Sonnax boost valve kits restore proper clearance with upgraded design and material to prevent EPC and Reverse boost loss. Increased performance and OE ratio kits are available.
Product Videos
Custom Field
Requires Tooling? No
