January 01, 2013

55-50/51SN Valve Body Identification

The transaxle is manufactured by Aisin Warner, but is used by many car makers. Volvo calls it an AW55-50, Nissan and Infiniti call it an RE5F22A, GM (Chevy, Saab, Saturn and Pontiac) calls it an AF33-5.

Part Number Chart

Vehicle TypeEarly/LateHas B5 SpringPart Number
GM/Saab/Saturn/SuzukiEarlyNo AW55GE
GM/Saab/Saturn/SuzukiLateNo AW55GL
GM/Saab/Saturn/SuzukiLateYes AW55GMLSP
VolvoEarlyNo AW55VE
Volvo/NissanLateNo AW55VL
Volvo/NissanLateYes AW55NL

Identify Vehicle Type

If vehicle type is not known check the S2 solenoid. A domed top on the S2 is a GM/Saab/Saturn/Suzuki. A flat top with four ribs radiating from the hole in the center of the S2 is a Nissan/Volvo.


Identify Early/Late

Look for a letter cast into the valve body to the right of the S4 solenoid hold-down bolt.
  • "No Letter/Blank Space" and valve bodies cast with a letter "A" are considered early.
  • Valve bodies cast with a letter "B" or "C" are considered late.


Check for B5 Spring

In model years '05-later, all Nissan and most GM/Volvo valve bodies may have a spring under the B5 control valve. It is very important to check the 10th digit of the VIN to verify production year. If the 10th digit of the VIN is 5 or higher, check your original valve body for a B5 control valve spring as shown. CAUTION: The wrong valve body will cause shift quality concerns.

Remove the two-bolt end plate as shown here and check under the B5 control valve to see if there is a spring.

SpringNo Spring

Related Units

Related Parts

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