The ATS 42RLE is engineered to hold the power and abuse Jeep owners can throw at it. Substantial increases in clutch pack surface area, line pressure and shift quality provide the reliability Jeep owners demand.
There are several things that should be understood about the 42RLE ATS built 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, reprogrammed clutch to clutch apply and release timing, 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.
Because of the combined combination of technologies we have used to redesign this transmission to handle extreme power levels we now offer the RLE for any application. If your looking for the best in performance, durability and over all shift quality you have found what your looking for.
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 horse power levels.
Rotating Clutch Drum Assembly and Clutch Packs:
Clutch modifications are generally one of the most impactive and important items that can be upgraded in any transmission. In the case of the 42-RLE transmission, there is little room for additional clutches so modifications must be done to pressure plates providing increased clutch surfaces.
The clutch surface area are 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 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 42-RLE 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. Also, the ATS 42-RLE valve body can be purchased separately and installed in a stock transmission for increased transmission capacity.