01M Transmission Master Rebuild Kit for VW Jetta and Golf

This is a master rebuild kit for the Volkswagen 01M four-speed automatic, referenced to part number 01M 325 429. It covers the clutch and sealing parts needed to overhaul the unit on the bench.

The 01M was the automatic behind most 1990s and early-2000s transverse VWs. Listed fitment: Jetta and Golf/GTI MK3 1994-1999, Jetta and Golf/GTI MK4 1999-2006, New Beetle 1998-2005 and New Beetle Convertible 2003-2005, Cabrio 1995-2002, Passat 1990-1997 and Corrado. Check the transmission code stamped on the case, since some of these cars came with other gearboxes.

The usual 01M story is a hard 2-3 or 3-4 shift, a flare between gears, or limp mode from clutch slip that the TCM reads as a gear ratio fault. Once the frictions are cooked, the fluid carries debris into the valve body, so plan to clean and inspect the valve body and replace the filter while the unit is apart. A worn K1 or K3 clutch pack is a common find on high-mileage units.

Refill with the correct VW-spec ATF and check the fill level at the specified fluid temperature through the check plug, not by volume alone. Reset adaptations after the install.