Aisin Warner AX15 Transmission Overview
The AX15 transmission is a 5-speed manual gearbox that was manufactured by the Japanese transmission firm Aisin Warner. Often called the AW AX15 transmission, or simply the Jeep AX15, this 5-speed manual gearbox was introduced half-way through the 1988 model year on the Jeep Wrangler YJ and Jeep Cherokee XJ. It is known to be much more durable than the Jeep AX5 transmission, and can withstand the torque output of many small V-8 engines. For 1994, a more conventional external slave cylinder and throwout assembly replaced the maintenance intensive internal slave cylinder unit. The 10 spline input shaft measured 1 1/8” in diameter, with a stickout length of 7 1/8”. The pilot tip was 19/32” until 1992, when it was changed to a longer 3/4” pilot tip.
What Transmission Do I Have?
OE AX15 5-speed Manual Transmission Applications
1988.5-1995 Jeep Wrangler YJ
1996-1999 Jeep Wrangler TJ
1988.5-1999 Jeep Cherokee XJ
1988.5-1992 Jeep Comanche MJ
1993 Jeep Grand Cherokee ZJ
1992-1999 Dodge Dakota
AX15 Technical Specs
Case: Cast aluminum split case with aluminum mid-plate
Input shaft: 10 spline x 1 1/8” diameter
Output shaft: 23 spline w/ 1/2” protrusion from the rear of the case (4WD)
Length: 16.5” (4WD)
Fluid capacity
Fluid type: 75W90 GL-3 gear oil
AX15 Transmission Gear Ratios
1st = 3.83
2nd = 2.33
3rd = 1.44
4th = 1.00
5th = 0.79
R = 4.22
Common AX15 Transmission Problems
Inability to engage reverse due to failed reverse gear. An updated design will be necessary.
What Transmission Do I Have?
Conclusion: AX15 Transmission
The Jeep AX15 transmission is known to be quite durable, and is particularly well-suited for off-road applications. A number of AX15 transmission adapter plates are also available, allowing you to marry this 5-speed manual gearbox to a number of General Motors and Ford V8/V6 engines.
