T98 4-Speed Borg-Warner Manual Transmission Parts for Jeep CJ5

Why the T98 Transmission in the Jeep CJ5 Wears Out After Decades of Use.

The T98 transmission was the go-to rugged 4-speed gearbox in Jeep CJ and Willys models for decades, prized for its heavy-duty construction. Despite that durability, typical wear appears after decades of use: seals on the input and output shafts harden and start leaking, letting gear oil escape and reducing lubrication of the gear set. Bearings on the mainshaft and input shaft wear out, causing whining noises or noticeable play. Gaskets at the shift cover, PTO cover, and transfer case adapter plate become brittle and start leaking. Nuts loosen from vibration, and the shift mechanism's poppet ball wears down from decades of shifting. Rebuilding your T98 or replacing individual wear parts noticeably restores smoothness and sealing.

• Bearings: The rear main shaft bearing and input shaft bearing keep the gear train running smooth and quiet.
• Oil Seal: The T18/T98 oil seal reliably seals the transmission against oil leaks.
• Gaskets: The transfer case gasket and the complete gasket and seal kit cover every sealing point.
• Mainshaft & Shift Mechanism: The mainshaft nut secures the mainshaft, and the poppet ball provides precise shifting.

Proven American Engineering for Your T98 Transmission.

All parts for the T98 transmission come from Crown Automotive, one of the leading American manufacturers of Jeep and Willys parts. Built to series-production quality, these reproductions meet OEM specifications and bring proven American engineering into your gearbox.

Your Partner for the T98 Transmission Rebuild.

Whether you're planning a full rebuild or replacing individual wear parts, we're happy to advise on installation order, torque specs, and the differences from the closely related T18 gearbox. We can also help with questions about the transfer case connection. Most items ship from stock and go out to you promptly.