Chrysler RFE transmission

The RFE is an automatic transmission family from Chrysler. The name refers to its Rear wheel drive design and Full Electronic control system. 45RFE and 545RFE The 45RFE was introduced in the Jeep Grand Cherokee in 1999, it is notable for including three planetary gearsets rather than the two normally used in a 4-speed automatic. It also features three multiple disc input clutches, three multiple disc holding clutches, and a dual internal filter system (one primary filter for transmission sump, one for the fluid cooler return system). In the 45RFE applications four gears are utilized. In the 545RFE four gears are used on the upshift and a new "gear", 2nd Prime, was used with a different (1.50:1 rather than 1.67:1) ratio to increase versatility when downshifting. Although, with some tuning, you can get the 545RFE to upshift into 2nd Prime. The 45RFE was produced at the Indiana Transmission plant in Kokomo, Indiana. It was normally paired with the 4.7 L PowerTech V8. The 45RFE later became the 5-speed 545RFE.