Putting Cherokee owners back in control of the 1-2 shift.
By Bruce W. Smith & Kevin Williams
Photos by Bruce W. Smith
Cherokee owners have undoubtedly felt the
frustration as their vehicles begin to
gain a little too much speed when going downhill. They reach down and drop the transmission lever into the 1-2 position, and then it happens: At about 12 mph, the transmission drops into First,
sending the shot-gun passenger into the windshield face-first and the rear passengers plowing into the front
Unfortunately, Jeep didn't engineer an easy way to lock the Cherokee's transmission into Second to prevent the sudden down-shift into First. A company named Aftermarket Innovations (Dept. OR, 4326 Glencoe St. NE, Salem, OR 97301, 800/528-6900) has a new product called the CompuShift Plus that successfully does this. CompuShift Plus is the brain child of Cherokee owner Jim Nasset, who experienced the sudden-shifting syndrome during a hunting trip and decided to invent this device.
The unit allows the driver to control the transmission computer by interfacing a separate control device that uses a Comfort/Power switch to manually control shifting into First and Second. The CompuShift Plus is activated when the transmission is moved into the 1-2 position. With the transmission mode switch set the Comfort position, the transmission will down-shift to Second and stay there until the Jeep is stopped.
|It will also take off from a dead stop
in Second (which is great on icy roads) but will downshift into First
when the gas pedal is depress more than one-third down. In
the Power mode, the CompuShift Plus stays out of the loop, letting the
transmission, respond as the factory had intended downshifting into
First at the factory's pre-programmed rpm. CompuShift Plus installs in
about five minutes by splicing into the factory transmission control
unit (TCI) under the dash on the right-hand side with 6 quick-splices.
We installed a test unit in an '89 Cherokee, which took about fifteen minutes to hook up, self-test, and photograph. Test driving entailed taking the Jeep to about 40 mph and then shifting into the 1-2 position with the CompuShift Plus in the Power position. The Cherokee down-shifted into Second with no problem and then on to First at approximately 28 mph. We repeated the test with the mode switch in the Comfort position and down-shifted again into 1-2.
The Cherokee responded with a smooth transition to Second and stayed there until the vehicle was stopped. This time the accelerator was depressed lightly and the Jeep pulled from a stop in Second. With a little more gas pedal, the transmission quickly responded with a energetic down shift to First and accelerated like normal. The CompuShift Plus retails for $169.95.
Manufacturers Note: The Power/Comfort switch was discontinued by Jeep in the 1992 year model vehicle. The CompuShift Plus kit includes a pre-wired switch for installation on the the 1992 and newer vehicles.