XJ Torque Converter Swap For Mileage And PowerPosted in How To: Transmission Drivetrain on May 1, 2012
We embarked upon our ’98 Cherokee project during a time of astronomically high gas prices. Our goal initially was to build it to go off-road while not losing any on-road commuter-type mileage. We’ve stayed pretty close to the original plan, but over the last year or so we’ve been underwhelmed by the performance we were seeing.
The transmission was getting too hot. Downshifting only made things worse. Then we started getting codes that the torque converter wasn’t locking up. Now, we knew the torque converter was hurting. We’d been hearing that death rattle every time we took the Jeep wheeling, and with 245,000 miles on the original transmission and torque converter, it was no big surprise.
But was a full transmission rebuild necessary, or was our torque converter the sole culprit as we suspected? We figured a torque converter swap could be done in a day. However, living 20 miles from the nearest parts store, and with no other Jeeps on hand if something went wrong in the driveway, we decided to enlist some expert help. We took the Jeep and the new torque converter down to Jeeps R Us in Laguna Hills, California. The crew had the install done in one morning, and we were back on the road before afternoon rush hour hit.
The results? Our suspicions were confirmed. Our gamble to change only the torque converter paid off this time around. We immediately noticed a seat-of-the-pants improvement in power, which the dyno verified. However, we were surprised to see that our power improvement didn’t translate into any increased mileage at the pump. So if your converter is chattery, your Jeep sluggish off the line, or your fluid temperature is inexplicably climbing, an inexpensive torque converter swap could buy many more miles for your automatic before a full rebuild is necessary.