T90 3-Speed Borg-Warner Manual Transmission Parts Willys M38A1
Bearings, Gaskets, Shift Knob & Hardware for Smooth Shifting (1952–1971).
Why the T90 Transmission in the Willys M38A1 Wears Out Over the Years.
The Borg-Warner T90 transmission is the heart of the drivetrain in the Willys M38A1, enduring decades of demanding field use. As a rugged 3-speed gearbox, it proved itself in military and off-road service, yet even careful maintenance cannot prevent wear entirely. Bearings on the input and output shafts develop play over the operating hours, seals harden and start leaking, letting transmission fluid escape and lubrication suffer. The mainshaft nut loosens from vibration, spacers wear down and alter bearing clearance, while the poppet ball in the shift detent loses tension through constant friction. The shift knob also shows visible wear over time. Anyone driving or restoring an M38A1 regularly should inspect and replace these wear parts in time to avoid shifting problems and consequential transmission damage.
- Gaskets & Repair Kits: The complete gasket kit for the 3-speed transmission and the more extensive transmission installation kit with bearings, seals, and small parts for a full overhaul.
- Bearings: The input shaft bearing including snap ring and the main shaft output bearing ensure smooth, play-free rotation.
- Mainshaft Hardware: The mainshaft washer and mainshaft nut secure the mainshaft, while the spacer maintains correct bearing clearance.
- Shift Mechanism: The shift knob and the poppet ball for the shift detent provide precise, reliable gear changes.
American Manufacturing Quality Across the Entire T90 Range.
All T90 parts for the Willys M38A1 come from Crown Automotive – one of the best-known names in American parts manufacturing. From bearings and gasket kits to shift knobs and small parts, this US manufacturer builds precise reproductions to OEM specifications, proven for years in classic vehicle restoration.
Your Partner for the Willys M38A1 Transmission Overhaul.
Whether you need a single wear part or a complete T90 overhaul, we're happy to advise on installation order, torque specs, and compatibility with related gearboxes such as the T14, T15, or T150, in case your M38A1 received a different transmission over the years. Your order ships from stock as fast as possible.