Rebuilding the Jeep Cherokee AX15 Aisin Manual 5-Speed
The Aisin AX15 transmission has been a popular offering
in the Jeep XJ Cherokee 4.0L models. A rugged, close-tolerance manual overdrive transmission, the AX15
provides the stamina needed for highway and off-road use. This is the disassembly of a unit with 200,000 service
miles. This gearbox core source is a 1990 XJ Cherokee.
Click here to quickly access 'Part 1' of the two-part article on the AX-15
Click here to quickly access 'Part 2' of the two-part article on the AX-15
4WD Hardware offers a blow-out diagram and available parts listing for the AX-15 transmission.
For direct access online, click here!
Caution: When purchasing synchronizer parts, make sure
you match the 3rd/4th gear synchronizer pieces. Aisin changed the bronze ring and sleeve design in the
late 1990s. Aftermarket rebuild kits may contain the earlier parts, which do not match the late synchronizer
pieces and will cause problems. See the forum posts for more details—links available in the "Note"
Note: You can gain a
valuable understanding of the AX15's functions by watching
YouTube video embedded at the forum posts on AX15 rebuilding issues. The presenter does an
excellent job of describing the functions of this transmission. You will find this video helpful. View it as you
diagnosis and follow my rebuild steps in this 2-part article! You also want to check out the synchromesh parts
design issue for the 3rd/4th synchronizer assembly on the late AX15 Jeep transmissions. There is an excellent discussion at the forums regarding "earlier" versus "late" 3rd/4th gear
synchro parts and a number of other AX15 issues, click
I have rebuilt manual and automatic transmissions professionally for more than four decades and believe the AX-15 transmission
is a quality gearbox for a stock 4.0L inline six or even a moderately modified engine in the
250-270 horsepower range. If your plans include a 4.5L to 4.7L stroker buildup of the 4.0L six, the AX-15
will tolerate reasonable use with that kind of torque output. The well-engineered gearbox has European
and Asian features, somewhat more sophisticated than a traditional, U.S.-design Jeep manual transmission.
Read through each step before rebuilding!
this step-by-step rebuild on my studio/shop work bench. Jeep owners and professional techs can clearly see each
detail of the AX-15 restoration, including the teardown, inspection and close-tolerance fit of parts during
assembly. Following sequence is everything with this transmission build. The result can be a
transmission that delivers quality service for decades.