Automatic Transmission

High Impact 47re/48re (A518/A618) “Bad Boy” 

for Dodge CUMMINS 

We have heard it said, "The Dodge Cummins is a million mile motor that beats the crap out of everything in the drivetrain after it" The factory automatic as used by Dodge behind the Cummins does not seem to be the rave answer to durability in use behind Cummins Diesels. Even stock, apparently, from what our customers are telling us. One answer many truck owners have resorted to in conversion to a manual trans. We have found conversion to an NV4500 to be a popular solution. However; When we began working on a "Bad Boy" auto trans to live behind the Cummins, we started with a monster: We had a customer that was making 6-700hp out of a Cummins, Towed a 25,000 lb trailer, and just HAD TO have an automatic.     

Our engineers got crackin', and developed the "BadBoy for Cummins".

We start with a Dodge A518 or A618 Trans casing and build from there. Inside that housing a transmission is built to take the power and load and live. 

There a number of standard upgrades used in Bad boy units, such as an upgraded HD torque converter with furnace brazed turbine elements and HD lock up clutches, oversize sprags, upgraded pressure regulator and reverse boost valve, and internal modifications for improved oiling and shifting. Units are specifically engineered to match the exact vehicle application they are to be used in, on a one at a time basis 

This transmission requires a computer for shift control. If you already have a Dodge Cummins truck with an A518 or A618,the Factory Dodge computer used in vehicles with a 518 or 618 trans 1994 and up will work. We will simply build you a "BadBoy" trans, and it will bolt in and hook-up as a direct replacement.

Retro fitting a computer controlled transmission in vehicles that did not come with the correct Dodge computer IS possible: Data below.

Power Capacity: 800 ft-lbs of torque, 800 HP. 

Full data on the controller we use: Powertrain Control Solutions TCM

Power Capacity: 800 ft-lbs of torque, 800 HP. 

Controlling Dodge 47rh / 47re / 48re without the stock ECM:

95 and earlier trannies (designated –rh)

The earliest version of the RH trans did not have a lockup converter. In 94 a lockup converter was introduced to the RH. Even though the RH is designated H, overdrive (and when present TC lockup) use solenoid(s) to turn on and off hydraulic fluid pressure to actuate these functions. These functions are controlled in an on-off electrical manner in a RH tranny. 

The 94 up trans with lock-up has a place in the trans for the lockup solenoid and has fluid passages that do not exist in the earlier non-locking 74RH

On these transmissions it is possible to use  a pressure switch on the governor pressure rail. Since governor pressure is directly proportional to vehicle speed, you can then set a speed for control.  Once the trans is locked into OD, it will not downshift even at full throttle until the lock is shut off. Thus a throttle position detent sw must be installed to open the circuit under full throttle so it will downshift. Another problem is the converter clutches in the 47RH will not handle high throttle or engine braking. So the above w would not be full throttle, it would need to be set at maybe 2/3 or 3/4 throttle to prevent clutch damage. And clutch engagement must be disallowed for engine braking so a zero throttle release sw must be put in. You will need  to get all this working and tweaked out so it works and the trans is reliable. It can be done. It is not something I can provide turnkey, and as it is fraught with many possible trans failure possibilities, I cannot guarantee it.

96-up trannies (designated –re) 

Were also not true electronic trannies, in that 1-2-3- shifts are still hydraulic controlled. They DID however - rather than use a cable to set throttle position control like they did in the –rh trannies – decide to use a PWM (pulse width modulated – a sort of digital control signal) to operate a pressure control solenoid in the valve body. This is not simply an on-off solenoid, it controls a variable pressure and REQUIRES a PWM driver to control it. So the above “analog system will not work.

 It IS possible to control this function with the Powertrain Control Solutions Transmission Control Module. There are two ways: 

1. You can use an aftermarket valve body with full solenoid control of shifting. With this valve body and the PCS TCM, you can get fully programmable electronic control of the trans, Cost appx $2k, incl ECM, wiring harness. The controller will come pre programmed for the application (“base calibrations” – a starting point program, where you can then tweek shift point to where you want them).

2. It IS possible to use the PCS TCM to control the TC lockup, OD engage and the PWM throttle position pressure control solenoid. This will NOT give you full electronic control of the trans, just these functions. This is defiantly not a full utilization of this controller. Kind of like using a backhoe to dig a 2 foot hole. PCS Does not supply any base calibrations for this. You will need to start with their “universal” harness, which means bare wires on the trans end, and you will need to wire on your own connector. You will need to program the controller to operate the needed functions. The controller will come with complete instructions on how to program it, but it will not come with the “base calibration” for this. So: It can be done, but you will need to do it from scratch. I have not done one myself. I have sold a couple of these. One went to France and I have not heard back from the guy. The other one: The guy says he will set it up this summer, and will pass on the data when he has it. Until someone figures this stuff out and passes it to me, I will not have the details. The PCS TCM is $750 and the universal wiring harness is $175

Full data on the controller we use: Powertrain Control Solutions TCM