The 42RE and 44RE transmissions used with 3.9-liter and 5.2-liter engines respectively have higher numerical ratios for first and second gears to enhance launch feel and low-speed passing ability compared to the 46RE transmission used with the 5.9-liter engine.

RFE stands for rear wheel drive, fully electronic. This is an electronically-controlled transmission with five forward ratios including an alternate second gear ratio for improved performance for passing and better fuel economy. It was designed for Jeeps but was used later in Dodge trucks; its first use was in the 1999 Grand Cherokee V8.

The transmission features a tall, 3.00:1 first gear that gives the driver better initial acceleration. Real-time driver adaptive shifting fine-tunes the shift pattern to the driver, while an alternate second gear ratio gives the driver five forward ratios. During acceleration, second gear has a ratio of 1.67. Depending on speed and throttle position, both this gear and an alternate 1.50 second gear ratio are available for kick-down operation, making the down-shift smoother. Its reverse gear ratio is equal to the first gear ratio, to allow for heavier loads.

Other features include three planetary gear sets that combine the widest range of gear ratios available in any transmission in its class. Combined with precise step selections, this brings smooth shifts and maximum power and optimal fuel economy.

The transmission is built at the Indiana Transmission Plant in Kokomo, Indiana, in an all-new 1.2-million square-foot facility.