*Volvo Transaxle & AWD Driveline Nomenclature – Technical Overview*
Volvo used several transmission families between 1999-2024. Getting the exact code right matters because bellhousing patterns, fluid specs, TCM software, and AWD coupling types all changed by platform and engine torque.
*1. Aisin AW55-50/51SN – 5-Speed Automatic | P2 Era*
*Full designation*: Aisin-Warner 55-50SN / 55-51SN 5-Speed Transverse Transaxle
*Volvo application*: V40 2000-2004, early V50/S40 2004-2006, S60/V70 P2 2.4, 2.5T, 2.5T AWD
*Torque capacity*: ∼330 Nm
*Construction*: Planetary gearset, 5 forward ratios, electro-hydraulic control with external TCM. FWD or Haldex Gen 2/3 AWD via bevel gear.
*Fluid spec*: JWS3309 / Volvo -8. Do not use Dexron VI.