BA10/5 (Early Peugeot) — The Bad One
Peugeot-built 5-speed used in 1987-1989 XJs. Notoriously weak. If you have one, swap it for an AX-15 or AW4. do it.
The BA10/5 (sometimes called Peugeot BA-10) was Chrysler's first attempt at a 5-speed in the XJ. Built by Peugeot, it shipped 1987-1989. The unit has a deserved reputation as one of the worst manuals in Jeep history.
Problems:
- Synchros fail by 60-80k miles
- Output shaft splines strip behind 4.0 torque
- 5th gear gets noisy
- Reverse engagement notchy from new
- Bell housing cracks at the t-case face
- Shifter feels like stirring rocks
The lifespan of a stock BA10 behind a 4.0L is typically 100-150k miles before it needs rebuild or replacement. Rebuild kits exist but parts are scarce and not cheap.
The answer: swap to AX-15 (89-99) or NV3550 (00-01). Both bolt up to the 4.0L bell with the same crossmember and t-case interface. A junkyard AX-15 with clutch and bell is $400-700. Total swap cost $800-1500. Worth every penny.
Identification: BA10 has a distinctive cast iron rear case and uses a 23-spline output to the NP231 (same as AX-15). The shifter base has a different boot and bezel. VINs from 87-89 XJ manual are likely BA10 unless previously swapped.
If you bought an XJ and the manual feels awful, check what trans you have. If BA10, plan the swap.
Why it works
- historical interest only
Trade-offs
- unreliable
- weak
- expensive parts
- bad shift feel
Tools required
- flashlight
- drain pan
Sources
Related
- AX-15 Manual Transmission Overview
- NV3550 Swap Overview
- AW4 Auto Transmission Overview and Durability
- All Jeep Cherokee XJ guides & tools
- Browse the full DIY database
Written and maintained by an AZ wheeler and driveway wrencher. How we source guides. Always cross-reference your factory service manual — modifications affect vehicle safety and warranty. Work at your own risk.