Transmission Parts Aisin AW 55-51SN 55-50SN Valve Body Valve / Sleeve

Symptoms:

Harsh downshifts
TCC apply & release concerns
RPM surge on coast
TCC codes
RPM surge on light acceleration
Overheated converter fluid

Cause:

Bore wear at the TCC control valve and/or sleeve results in the torque converter clutch remaining applied and transferring the shift shock. Loss of TCC control also results in RPM fluctuation.

Correction:

Sonnax oversized lockup control valve and boost assembly kit corrects circuit pressure loss and restores control of the TCC lockup circuit.

Warning:

Required tool kit F-59947-TL29 is no longer in production. Check with your distributor for availability.

55-50SN, 55-51SN

Oversized Lockup Control Valve & Boost Valve Kit
Part No. 59947-29K

Also fits AF23/33 and RE5F22A units.

Tooling:

F-59947-TL29
F-15741-TL29PL
VB-FIX

You need this if... View Instructions Find a Distributor

In Aisin AW 55-50SN and 55-51SN units, bore wear at the lockup control valve in listed units results in loss of torque converter clutch control. The TCC can remain applied transferring shift shock, or loss of lockup control can result in RPM fluctuations. Sonnax oversized lockup control valve and boost valve kit 59947-29K restores control of the TCC. Proper TCC control eliminates the shift shock and RPM fluctuations associated with a worn lockup control valve.

Hardcoat anodized aluminum valves combat premature wear
The boost sleeve is highly wear-resistant to increase life

Note

F-15741-TL29PL is required for securing small No. 2 rear control valve body to VB-FIX.

Contents

Lockup Control Valve
Boost Valve
Boost Sleeve
Boost Spring

Valve Body Layout

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.