Aisin AF33 transmission

The Aisin AF33 is a 5-speed automatic transaxle developed and manufactured in Anjo, Japan by Aisin AW, a division of Aisin. It is designed to be used in transverse engine configurations in both FWD and AWD configurations.

The actual model codes are AW55-50SN and AW55-51SN. Manufactures have sometimes chosen own designations such as AF23, AF33 or AF33-5 (GM),RE5F22A (Nissan and Infiniti) or SU1 (Renault). Other manufacturers use the original designation(s) or minor variations of it such as AW55-50 LE (Volvo), AW 55-51 LE (Opel) and FA57 (Saab).

Several manufacturers list the transmission in their owners manuals as fill for life, meaning that there are no scheduled transmission fluid changes under normal operating conditions.

Transmission experts recommend regular fluid changes for severe driving condition, every 80,000 miles. Specific fluid must be used. If incorrect fluid is used it could result in improper operation and lead to transmission damage.

Aisin recommand to follow the scheduled maintenance. A badly done oil change can destroy the transmission.

Fluid must meet the JWS 3309 specification. The fluid can be found under varying designations.

GM Saturn: Aisin AF23/33-5 type T-IV P/N 889009250 (in Canada, P/N 22689186). Volvo AW55-50/51SN P/N 1161540-8. Nissan RE5F22A Nissan Matic "K" Fluid capacity 8.2 qt. (7.8L) Synthetic.

Exxon/Mobil manufactures a specific synthetic mineral fluid for this transmission simply called "3309".

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