6L45, 6L50

Symptoms:

• Erratic line pressure
• High line pressure
• Low line pressure
• Clutch slippage
• Harsh shifts
• Low cooler flow
• No cooler flow
• Overheated transmission
• Soft shifts
• Converter concerns

Cause:
Continuous oscillation of pressure regulator valve results in excess bore wear, causing erratic line pressure and/or restricting cooler/lube flow.

Correction:
Recover hydraulic control and renew line pressure performance by installing Sonnax drop-in pressure regulator valve kit.

GM 6L45, 6L50, 6L80 and 6L90 units may exhibit multiple line pressure and cooler/converter/lube flow problems due to excess wear in the pressure regulator bore. Deterioration at the balance spool end allows critical fluid loss, resulting in high line pressure, harsh shifts and overheating due to reduced cooler/converter flow. Wear at the outboard spool robs converter feed pressure and lowers line pressure, resulting in soft shifts and burnt clutches.

Installing the Sonnax pressure regulator valve kit restores the hydraulic integrity of these circuits for proper line pressure control in all ranges. A new pressure regulator valve outer spring is also included to replace weakened original springs and provides a modest 5 psi increase across the pressure curve.

• Hardcoat anodized aluminum valve combats premature wear
• Lengthened critical spools operate in non-worn portion of bore for added stability and wear prevention.
• Annular grooves help center valve in bore to reduce future side-load wear
• Replacement spring provides modest 5 psi line pressure increase
• No pump drilling required
• Drop-in Zip Valve™ parts install quickly and easily

Contains:

• Valve
• Spring
• Checkball

SONNAX Installation Instructions