One problem related to automatic transmission has been reported for the 2012 Jeep Wrangler. The most recently reported issues are listed below.
Automatic transmission with 'electronic range select' allows a downshift with a move of the shift lever to the left when in 'd' drive. A move to the right up-shifts. Accidental downshifts occur frequently because of 'hair-trigger' nature of shift lever controls. The slightest, barely perceptible movement left causes a downshift, often unintended and unexpected. Up-shifting requires a definite movement to the right. Discussion of this issue with 2012 automatic Wranglers drivers on Jeep internet forums suggests a number of people experience and have a problem with this, while a number of drivers state their shifter requires a definite move left to downshift. I experience frequent, accidental downshifts on every trip due to this defect. Current mileage on this vehicle is 1100 miles. Sudden deceleration due to accidental downshifts can cause loss of traction on unpaved, gravel, icy or snowy roads, confusion, disorienting, and over-revving the engine.