There are many things that need to be understood about the RAM 68-RFE transmission. This transmission was originally designed to be very inexpensive to manufacture. This approach forced the original designers to cut corners in size and quality of materials that could be used. On a positive note, the technology that is utilized in the transmission is leading edge; this advanced technology has forced the aftermarket to completely rethink how to modify and control the transmission so that it can still perform and remain reliable while modifying the engine to have higher power levels over stock. ATS has developed a combined technology utilizing recalibration of the hydraulic circuits inside the transmission, including revamped accumulator rates, reprogramed clutch to clutch apply and release timings, and line pressure rise rate to perfectly match the torque output of the engine. These enhancements, along with other key hydraulic modifications which ATS makes, must be done to ensure the clutch packs have the correct apply and release rates when commanded on or off. As well, the transmission hard parts have many limiting weaknesses which do not allow for increased power levels over stock. Specifically, the light duty shafts and hubs, and the low one-way sprag; these hard part weaknesses must be addressed. Some of the areas that are addressed by ATS to complete the performance transmission upgrade package are listed below, starting at the front of the transmission working towards the back.

The torque converter regulator valve has been redesigned to prevent over pressure and ballooning of the converter, along with regulating minimum converter charge for proper cooling and lubrication of the transmission gear set. This redesign also eliminates the common problematic valve and bore ware that is usually the first cause of high mileage transmission failure. The main pressure regulator circuit is modified to enable a broader range of pressure that can be commanded from the TCM. This allows the pump to lower line pressure when the engine is at low loads and more responsively raise pressure above stock to react with increased engine torque and horsepower levels.

Clutch modifications are generally one of the most impactive and important items that can be upgraded in any transmission. In the case of the 68-RFE transmission, there is little room for additional clutches so modifications must be done to pressure plates providing increased clutch surfaces. The clutch packs that are increased surface area listed below. The Under Drive (Forward) clutch pack surface area is increased by 21%, using single sided clutch plates. The Over Drive clutch pack surface area is increased by 17%, also using single sided clutch plates, this allows for better clutch control when overdrive is used at higher power levels. The 2C clutch pack surface area is increased by 34%, using double sided frictions. The 4C clutch pack surface area is increased by 34%, using double sided frictions. The weak mechanical low one-way sprag is replaced with a stronger roller clutch design that used a "cam and roller" system. The factory low sprag not only has a very weak torque capacity, but it also fails from lack of proper lubrication. The stronger low roller clutch design used by ATS prevents the higher mileage failure associated with the sprag-type clutch.

Although the new "cam and roller" low roller clutch design is much stronger it still has imitations; the Co-Pilot^® transmission controller contains a direct function to route power around the mechanical clutch when extreme power levels are sensed. You will read more about this in the Co-Pilot section below.

The valve body is considered the nervous system of the transmission; the valve body is responsible for converting the electrical signals from the TCM into hydraulic actions. The 68-RFE uses a non-synchronous, clutch-to-clutch design. This means that the shifts from gear to gear must be timed perfectly thereby releasing and applying a friction clutch to achieve an flawless shift. Because of the sensitivity of the hydraulic circuits, we heavily modified many areas of the valve body. Hydraulic oil flow is ported to certain clutch packs where additional pressure is needed. The accumulator piston seals have been redesigned to ensure hydraulic pressure integrity. The accumulator plate is made of high-grade material to compensate for the additional pressure that the accumulator pistons and springs exert during heavy power situations. 

 

Billet Channel Plate Valve Body Features:

• 1" thick billet-machined aluminum channel plate with enlarged critical channels
• Increased fluid to clutch packs
• Includes pressure testing ports

There are three shafts in the 68-RFE that are of some concern. The forward hub/shaft, Intermediate hub/shaft and the input shaft. The forward hub/shaft is reinforced to eliminate breakage. The Intermediate hub/shaft is reinforced to eliminate breakage. The billet input shaft is an optional upgrade included in stages 2, 3, and 4, and is made made from 300M billet material just like our 47-RE and 48-RE shafts.

The main transmission case does not require a lot of conditioning aside from a few small hydraulic modifications to allow for proper oil flow. At higher power levels the transmission case does need to be strengthened. This is a simple fix that is taken care of with the optional heavy-duty transmission pan, which was designed in part to act as a girdle, thus eliminating the flex in the case. The large over sized pan also provides for an additional 5 quarts of ATF allowing the transmission to run cooler.

 

Co-Pilot TOW Edition Transmission Controller Kit for 2007.5-Present Dodge with 68RFE Transmission, Plug and Play Line Pressure Controller The 68-RFE is plagued by small clutch packs, weak hard parts, constant slip torque converter lock-up, and inadequate line pressure. Typically, these issues can result in the failure of the stock transmission with just a mild tune or heavy trailer. The Co-Pilot Tow Edition addresses these concerns.

What the ATS 68-RFE Co-Pilot is:
The Co-Pilot consists of a controller, harness and secondary electronics box. The harness plugs into the main transmission connector on the valve body. The harness is completely plug and play for easy installation. The controller mounts in the cab and allows the driver view critical transmission and engine inputs such as line pressure, commanded engine loan and actual engine load. To view the different sensor inputs all you do is depress the up or down arrows. These changes can be made on-the-fly or with the vehicle stopped.
The secondary electronics box is mounted to the drivers side frame and requires no cutting or fitting.

What the ATS 68-RFE Co-Pilot Does:
The Co-Pilot controls line pressure, clutch timing and more aggressively applies the converter clutch under high torque situations. Line pressure is limited in a stock 68-RFE to 160 PSI. Unfortunately, this is not high enough to reliably prevent clutch slippage above 400hp. The Co-Pilot reads boost pressure and throttle position to quickly take control of line pressure when it is needed. However, when the vehicle is driven lightly, line pressure is near stock for comfortable shifts. This is all done automatically in the controller.
Line pressure is increased dramatically with the addition of a Valve Body Full Pressure Enable Kit. This kit is installed on any 68-RFE transmission built in house at ATS.

The kit can also be installed on a stock transmission to safely allow line pressure to increase to 270+ PSI. While the installation of the kit isn't necessary, it will increase the performance of the Co-Pilot to its fullest potential. We recommend installing one of our modified valve bodies to fully address all of the internal hydraulic issues with the 68-RFE Valve body.

The Co-Pilot has a huge advantage over TCM programing on 2013 and newer trucks because of the way the factory TCM is designed. When the higher line pressure modifications are done to the Valve body on a truck that is 2013 and newer aftermarket TCM tuning that is used will cause a radical pressure variation that spikes line pressure causing lots of problems. For this reason you will fine TCM tuning is not desired on these newer truck and when TCM tuning is used the tuners do not allow for full line pressure increases like the Co-Pilot does, the Co-Pilot utilizing its dynamic closed loop control addresses this with an averaging circuit that provides a very smooth and controllable line pressure rise up to 270PSI.

Clutch timing is programmed into the Co-Pilot and crucial to clutch pack life. On any 68-RFE transmission, clutch timing is optimized to reduce wear on clutch packs, efficiently transfer power and increase reliability.

The torque converter lock-up apply on a stock 68-RFE leaves a lot to be desired. The factory TCM will command lock-up at a very low speed when at light throttle, this causes a sluggish condition, low boost and poor drivability. The ATS 68RFE Co-Pilot will more firmly lock the converter clutch during apply, this allows the inherent torque of the Cummins engine to be used for better efficiency and performance.

Modes Available in Co-Pilot:
Setting 1 (down or all the way to the right)
This mode shows you what the position of the TPS is. No Lights=0 percent and 5 lights=100 percent
Setting 2 (One position from far right)
This mode shows you what the Boost sensor is seeing. No Lights=0 PSI Boost and 5 lights=40 PSI Boost
Setting 3 (Two positions from the right)
This mode shows you what the actual transmission line pressure is No Lights=100 PSI line pressure and 5 lights=260 PSI Line pressure.