The 66RFE transmission is the big brother for the 45/545RFE transmission. The RFE platform was initially created by Chrysler and was released in 1999 Along with the debut of the new Jeep Grand Cherokee. Most transmissions in modern cars use synchromesh to synchronise the speeds on the input and output https://autostartak.com/top-reasons-to-choose-quality-transmission-service-at-your-behest/