6L90

Symptoms:

• Overheated fluid
• Failsafe mode
• Harsh shifts
• Harsh TCC apply
• Loss of fuel economy
• Code P0741, P0742
• High TCC slip RPM

Cause:
Bore wear at the TCC regulator valve reduces TCC apply and converter charge pressure. A stuck TCC regulator valve causes either TCC slip or harsh apply.

Correction:
Sonnax drop-in TCC regulator valve kit has extended spool lands to operate in unworn areas of the bore and a lengthened shuttle valve to prevents the valve train from sticking.

ehicles with GM 6L45, 6L50, 6L80 and 6L90 transmissions may have a number of TCC apply problems. Bore wear at the TCC regulator valve can cause no TCC apply or slipping on engagement, harsh shifts, loss of performance and fuel economy and fluid overheat. If the valve is stuck in the apply position, the result is harsh TCC apply. If the valve is stuck in the release position, no TCC apply or TCC slip will result.

For moderately worn bores, installing this Sonnax TCC regulator valve kit will restore proper valve function resulting in proper TCC apply. The valve lands have been lengthened significantly, allowing the valves to operate in unworn portions of the casting bore to effectively seal against leakage.

• Hardcoat anodized aluminum valves combat premature wear
• Inboard and outboard spools on the TCC regulator valve have been made significantly longer to operate in unworn portions of the casting bore
• Outboard shuttle valve has been made longer for better sealing and to prevent cocking in the bore
• Restores proper valve function and TCC apply
• Drop-in Zip Valve™ parts install quickly and easily

Contains:

• Regulator Valve
• Shuttle Valve
• End Plug
• Spring

32782K Instruction Sheet