2012 Ram 2500 ATS Transmission Rebuild
A Tow-Rig Slushbox Rebuild
When it comes to our tow rigs, we want them to reflect our interests and personality. We want them to work for what we need them for. We also need them to be unquestionably reliable. In fact, the precise reason for owning a tow rig is to know that you will have a comfortable, dependable ride home even when the trail rig is worn, broken, or bent.
For those reasons it’s a good idea to trust your tow rig’s transmission rebuild to the best. When it comes to diesel truck transmissions, ATS is at the pinnacle of performance and reliability. Making sure that you know which doohickey goes where, and what that widget does and how to make it more reliable, does not even have to cross your mind. To this end, we rushed out to Denver, Colorado, and followed along as the auto transmission ninjas at ATS showed us the process of making a worn-out “stock” slushbox better than it ever was.
We followed a tow rig transmission job that’s common among our readers, a Dodge 48RE being transformed into a more power-hungry unit. Now don’t quit reading this if you drive a Bow Tie or a Blue Oval. ATS also has a high-performance transmission option for your GM or Ford tow rig—or race truck. While the parts may not be the same between different makes and models of transmissions, the rebuild is similar and the attention to detail and use of high-quality components won’t vary when a transmission passes through ATS’s capable hands. With six available build stages for the company’s transmissions, ATS can match a tranny to your truck and what you do with it, from daily driver to full race truck.
We started our day at ATS as Robert Shaw tore down a 48RE in preparation for a full ATS rebuild. This transmission was a core with relatively high mileage. We thought the transmission internals looked pretty good until we came across the intermediate or kickdown band, which showed evidence of wear and excess heat. Inside the direct drive drum, scorched clutches were found. This band is probably just worn out from mileage. It’s possible that tightening the band a few years back could have improved the transmissions function for a while, but this would have not extended the service life of the transmission. Also, if the band were overtightened it might have damaged the direct drive drum.
Inside the direct drive drum we found these scorched clutches. The dark or blackening clutch material indicates excess heat within the drum. This could have been related to the heat from the intermediate/kickdown band, or just wear. We also found that the cage for the transmissions sprag or low/reverse one-way clutch was broken. Otherwise everything looked fine within the transmission.
Once disassembled, the transmission and reusable parts are steam-cleaned before the case is painted in ATS purple. Vince Santos begins the rebuild by cleaning gasket surfaces of the transmission housing. Each transmission is assembled by hand by one of ATS’s technicians. Any used parts that are reinstalled are once again checked by the assembler, and if there is any question of damage a part is replaced with a new or undamaged used part.
One other way that ATS adds strength and reliability to the 48RE is by machining the pressure plates in the transmission. That allows the addition of extra clutches and steels. This means less friction for each individual clutch, thus the transmission is stronger. Dan Walters installs clutches and steels in the front drum.
The valve body of an auto tranny is where many strange things happen. Santos uses a flat sanding table to ensure that the valve body is truly flat and not at all warped. This will ensure a good seal and proper function. ATS modifies the valve body with heavy-duty components and drills out a few locations on the stock body for performance much like a shift kit, only to ATS’s high standards. Again, any worn parts will be replaced.
Several parts in the 48RE’s valve body are upgraded per ATS’s requirements. They machine out part of the body and press in a steel sleeve in the valve body’s throttle valve to resist wear much better than the original aluminum of the housing.
ATS even goes so far as to reengineer parts within the transmission that are not up to par. This includes redesigning the unreliable Dodge governor solenoid with a new casting and a more dependable GM solenoid shown here below the failure-prone stock component. The GM solenoid is capable of dealing with higher line pressures.
Because of the extra clutches ATS installs in the different drums, it is important to measure the endplay of the transmission. A jig allows for quick and easy endplay adjustment.
Once the transmission is nearly assembled, compressed air is used to adjust the band tightness. Another cool upgrade part that ATS installs in every rebuilt 48RE is this billet band tensioning strut (stock stamped part below). ATS also offers billet intermediate, input, and output shafts that are built to withstand greater loads and stresses than factory parts. ATS’s Extra Deep Transmission pan carries more transmission fluid and acts as a large heat sink to keep temps down. Heat is the enemy of all auto transmissions, so keeping things cool improves longevity and performance.
Once the transmission has gone through the rebuild it is bolted to a transmission dyno and run for 20 minutes while all gears are tested and pressures checked. If something does not function as expected the transmission will be disassembled to find the failure and repaired. Only after the transmission has passed the dyno inspection will it be installed or shipped to the customer or one of ATS’s authorized installation facilities.
ATS’s 5-Star Torque Converters for the Dodge 48RE are not just another rebuilt converter. They are packed full of parts that have been reengineered and seriously beefed up. This includes the two-piece billet cover, patented Viscous clutches (the stock converter has one clutch while ATS’s have three), a proprietary stator, secured impeller and turbine vanes, and a hardened pump drive hub. Stall speeds are matched to your Cummins engine, and custom stall speeds are available for racing or pulling applications. Also notice how the stock torque converter bolt holes are tack-welded to the converter. Those can work loose, but the billet ATS part would have to literally blow apart before the converter broke free from the engine.
In order to maximize the performance of your diesel truck, your turbo system should be matched to your converter and your transmission, transmission lockup, and shift points. One way to do this is with an ATS trans, an ATS torque converter, and an ATS’s Co-Pilot. The Co-Pilot controls line pressure and torque converter lockup to maximize the performance of your truck’s new ATS-built transmission. By adjusting the Co-Pilot you can time converter lockup for compression breaking with your exhaust brake. The Co-Pilot also fine-tunes line pressure and lockup during shifting to improve the efficiency of power transfer without harsh shifting, maximizing the performance of your ATS-modified truck. Sure, the Co-Pilot can be used with a stock transmission, but without the additional strength from ATS shafts and other components a stock tranny can fail under heavy loads or the high-performance shifting associated with the Co-Pilot.