ATS Diesel Performance New! 4R100 Transmission Conversion Cummins 6.7L
4R-Performance transmission over any Stock or performance built 68-RFE is ultimate reliability and price. The 68-RFE transmission has some great qualities but unfortunately it suffers in several areas that can not be easily overcome.
Our performance built 68 RFE Transmission with the Co-Pilot installed is great at power levels up to about 600 RWHP, although we have several trucks out there that are 900+ the 68-RFE is not the favored choice for that power level. Here are a few conditions that we have a difficult time dealing with when it comes to the 68-RFE "clutch to clutch" transmission.
First off the 68 clutch apply and release is 100% computer controlled. That means every time a clutch pack is applied or released the computer must control the exact clutch apply rate and the exact clutch release rate during the shift with exact precision or one of the two clutch packs being applied and released will be damaged. This is the real issue with the 68 transmission. There are 5 clutch packs in the 68 transmission that are responsible for all forward and reverse gears. If two clutch packs are applied you get one of 6 forward gear ratios, if one is applied you get no movement and if three are applied you get a bind-up or clutch drag! It is just short of a miracle that the Dodge TCM can adapt to such changing conditions that effect clutch to clutch application rates as well as it does.
Here are a few of these changing conditions, fluid temperature, engine load, power level, throttle position, clutch coefficient, line pressure, internal hydraulic leaks, internal clutch clearance, solenoid resistance, wiring fatigue, corrosion, battery voltage, humidity, vibration, and the list goes on and you get the point. This is all wrapped around the envelope that the engineers calculated to be the environment that the 68 transmission would live in.
4R100 Conversion Kit For 2007.5-2013 Dodge
This is why the 68 is relatively reliable in a bone stock truck using factory stock calibration. As soon as you increase power to the engine by installing a tuner you go beyond the ability for the TCM to accurately calculate the clutch volume index (CVI) of each clutch pack. CVIs are used by the TCM so it knows the clutch pack clearance of each clutch pack. The TCM must know the clutch pack clearance so it will know what CVI number to plug into its algorithm to accurately apply and release the on and off going clutch pack. The TCM must do this correctly every time under all power levels to ensure a consistent shift takes place.
Where the 68 gets into trouble, We deal with all this nonsense by placing the Co-Pilot between the TCM and the transmission and apply another level of input (True engine load) to the TCM and take control of the transmission. This allows our Built 68-RFE to reliable and consistently handle up to 650 RWHP without the negative effects as long as the rest of the factory electronics are in good condition. As you can see 68 transmission is a slave to the outside environment and is very venerable to so many possible problems that can and does often cause total transmission failure in a very short time!
The 4R100 Advantage
First off, the 4R transmission is a synchronous type transmission which means there is no "clutch to clutch" timing issues that need to be dealt with by the computer! This in it self lay the foundation for a brutally reliable transmission package! Shift quality is much better controlled by the 4R trans, all shifts are actuated by an on/off shift solenoid that passes clutch application through a clutch fill valve that also has an accumulator to better control clutch fill time allowing for precise clutch application.
This provides a near perfect shift at all power levels. The gear ratios of the 4R Transmission are evenly spaced providing a consistent RPM drop between all shifts. This consistent RPM drop gives a smooth power transfer while reducing the air disturbance through the turbocharger maintaining even boost levels. The Torque converter clutch (TCC) application is a modern day type Pulse Width Modulation (PWM) signal that provides smooth controllable TCC application. All this combined adds up to a transmission that shifts through all the gears and applies the TC with smooth accurate operation.
This kit is complete ready to install