Symptoms:

  • Soft shifts
  • 延迟的变化
  • Delayed engagement
  • TCC apply & release concerns
  • Harsh shifts

Cause:

Wear at multiple points in the pressure regulator bore causes loss of pressure control.

Correction:

Sonnax oversized pressure regulator and boost valve kit includes an oversized pressure regulator valve to restore correct clearances for proper hydraulic control, and a replacement boost valve assembly

Warning:

Required tool kit F-59947-TL12 is no longer in production. Check with your distributor for availability.

55-50SN,55-51SN

Oversized Pressure Regulator & Boost Valve Kit
Part No.59947-12K

Also fits AF23/33 and RE5F22A.


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

In Aisin AW 55-50SN and 55-51SN units, wear at the balance end can cause harsh shifts, high line pressure, converter apply/release problems and lube-related issues. Wear at the other locations can result in soft shifts, low line pressure, and converter problems. Boost sleeve wear reduces the ability of line pressure to rise according to TCM command, resulting in slow line rise and late shifts. Late shifts can often create gear ratio codes. A worn boost sleeve in this unit can also cause a delay in reverse or slippage, eventually burning the low reverse (B3), 1-2 reverse (B5) band and or the direct clutch (C2). Sonnax oversized pressure regulator and boost valve kit 59947-12K restores hydraulic integrity.

  • Hardcoat anodized aluminum valves combat premature wear
  • The pressure regulator valve has longer length spools for increased valve support.

Check step location of OE retainer first, and note. Use same height step on replacement valve.

  • Pressure Regulator Valve
  • Pressure Regulator Spring
  • Boost Sleeve
  • Boost Valve

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.看到所有Sonnaxvalve body layouts.

Aisin AW 55-50SN, 55-51SN Valve Body Layout

Aisin AW 55-50SN, 55-51SN Valve Body Layout
  • 55-50SN, 55-51SN Oversized Pressure Regulator & Boost Valve Kit 59947-12K
  • 55-50SN, 55-51SN Oversized Pressure Regulator & Boost Valve Kit 59947-12K

You need this if...

Vacuum testing at the port(s) indicated fails to hold the recommended minimum in-Hg, or if wear is visually detected.

55-50SN, 55-51SN Oversized Pressure Regulator & Boost Valve Kit Vacuum Test Locations
55-50SN, 55-51SN Oversized Pressure Regulator & Boost Valve Kit Vacuum Test Locations