When Dodge introduced the Cummins engine, it represented a major breakthrough in power, torque, and fuel economy for Dodge pickups. It also was the beginning of what would turn out to be an ongoing struggle with transmissions. Before long, the word was out: Dodge transmissions weren't always able to stand up to diesel torque, especially in heavy-hauling or towing applications. Subsequently, the factory began implementing minor improvements in an effort to stem the tide of transmission warranty claims, finally getting it right only a couple of years ago.
| BD tests every transmission it builds on an in-house transmission dynamometer. The technician makes sure the unit is performing correctly through a variety of tests before it is shipped to the customer.
One thing the factory didn't concern itself with, however, was the burgeoning diesel performance market. While the latest Dodge transmission, the 48RE, was able to handle the stock power levels, failure began to shake its ugly head when power was increased beyond 60 hp or so. It soon became evident that with engines that were capable of more than 1,000 lb-ft of torque, something had to be done, and BD Diesel Performance has done it.
BD has been at the forefront of the diesel industry since it began, offering an ever increasing line of performance products to answer the needs of the evolving Cummins market. As problems with the Dodge 47RE and 48RE transmissions began to surface, the company initiated an extensive research and development program to determine the weak links in these transmissions, and then methodically solved them to arrive at some truly dependable designs. Today, BD offers everything from exchange transmissions to custom-built race transmissions and torque converters, made on the premises and designed to handle the outer limits of diesel torque. They even back their transmissions with a one-year parts, labor, and freight warranty, and offer an optional three-year warranty as well.
We visited BD to learn what they do to their transmissions to make them live behind high-torque diesel engines. From the torque converter to the tail shaft, BD's transmission department walked us through the mods that they perform. As you'll see, they amount to much more than a recalibrated valvebody and some extra clutches; these transmissions are literally reengineered. And though we're focusing on Dodge transmissions in this article, it's worth mentioning that BD offers the same services for the current crop of Ford and GM transmissions as well.
If you plan to bolt serious horsepower onto your diesel, save yourself some trouble and consider a performance transmission designed to handle it. The factory may be able to experiment with the thresholds of transmission failure, but we're betting you can't afford to do the same.
