July 01, 2020
Always Identify These Valve Bodies BEFORE You Start a Transmission Rebuild
Andrew Jessiman
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 Type | Early/Late | Has B5 Spring | Part Number |
|---|---|---|---|
| 通用汽车/萨博和土星/铃木 | Early | No | AW55GE |
| 通用汽车/萨博和土星/铃木 | Late | No | AW55GL |
| 通用汽车/萨博和土星/铃木 | Late | Yes | AW55GMLSP |
| Volvo | Early | No | AW55VE |
| Volvo/Nissan | Late | No | AW55VL |
| Volvo/Nissan | Late | Yes | 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.
| 通用汽车/萨博和土星/铃木 | Volvo/Nissan |
|---|---|
 |
 |
Identify Early/Late
Look for a letter that is 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 2-bolt end plate and check under the B5 control valve to see if there is a spring.
| Spring | No Spring |
|---|---|
 |
 |
Learn More
Related Units
Related Parts
Required
Recommended
55-50SN, 55-51SN
Remanufactured Valve BodyAW55GE
GM, Early, “A” or No Letter Casting
Required
Recommended
55-50SN, 55-51SN
Remanufactured Valve BodyAW55GL
GM, Late, “B” or “C” Casting, without B5 Spring
Required
Recommended
55-50SN, 55-51SN
Remanufactured Valve BodyAW55GMLSP
GM, ’05-Later, with B5 Spring
Required
Recommended
55-50SN, 55-51SN
Remanufactured Valve BodyAW55NL
Volvo/Nissan, ’05-Later, with B5 Spring
Required
Recommended
55-50SN, 55-51SN
Remanufactured Valve BodyAW55VE
Volvo, Early, “A” or No Letter Casting, without B5 Spring
Required
Recommended
55-50SN, 55-51SN
Remanufactured Valve BodyAW55VL
Volvo/Nissan, Late, “B” or “C” Casting, without B5 Spring
While Sonnax makes every effort to ensure the accuracy of technical articles at time of publication, we assume no liability for inaccuracies or for information which may become outdated or obsolete over time.