BD Diesel Automatic Transmission Torque Converter

BD Diesel Torque Converters: Engineering Built for Diesel Demand

When a modified diesel engine produces two to four times its original torque, the stock torque converter becomes the weakest link in the drivetrain. BD Diesel has spent decades solving exactly that problem, earning a reputation as one of the most trusted names in heavy-duty automatic transmission torque converters for light-duty diesel trucks. Their dedicated Transmission and Torque Converter Department focuses entirely on the development and analysis of diesel drivetrain components, bringing engineering discipline — including CAD and FEA simulation — to every converter they produce.

Signature Product Lines

BD Diesel’s torque converter lineup spans several distinct product tiers, each targeting a different performance need:

• ProForce 3D Multi-Disc Converter — BD’s flagship converter for Dodge Cummins applications (covering 5.9L and 6.7L engines), the ProForce 3D features an in-house CNC-machined billet cover designed to prevent warping and maintain proper balance. Its engineered cast stator uses optimized fin lengths, angles, and curvatures to deliver fluid coupling efficiency of up to 95% — compared to roughly 75% with factory stators — which reduces engine temps, improves fuel economy, and puts more torque to the ground. A self-centering trapezoid clutch teeth design ensures proper alignment and reduces wear for a longer converter life cycle. The ProForce 3D is also available in multiple stall speed configurations: enhanced stall for street or towing, low stall for street use with stock tires, and high stall for race, drag, or sled pull applications.
• Triple Disk / Triple Force Converters — Designed for higher-horsepower builds, BD’s triple disk converters feature raised teeth into which multiple clutch discs stack for maximum torque handling capacity, along with a beveled, double-ring cover plate construction engineered for extreme clamping strength.
• ProForce Converters (Classic) — Available for early Dodge 5.9L Cummins applications (including 727/518 transmissions), these converters incorporate Torrington thrust bearings to replace inefficient factory wear washers, resulting in noticeably reduced stall speed, more positive engagement in drive, improved low-speed drivability, and better fuel economy on the street.

Why BD Diesel Stands Apart

BD’s converters are not just rebranded aftermarket units — they are purpose-engineered components backed by a company that also builds the transmissions they pair with. BD also employs a double cage stator sprag design on select Allison-application converters to reduce common stator failures seen with OEM designs. The ProForce 3D even manages to reduce overall converter weight compared to competing units, which further contributes to better fuel economy and reduced drivetrain wear. Coverage spans the three major domestic diesel platforms: Dodge Ram Cummins, GM Duramax/Allison, and Ford Powerstroke, making BD one of the few manufacturers with a truly comprehensive torque converter program across all major diesel truck lines.

For diesel owners who tow heavy, run added horsepower, or simply want a more responsive and durable converter than what came from the factory, BD Diesel’s automatic transmission torque converter lineup represents one of the most engineering-intensive options on the market. Explore the full BD Diesel brand page to see their complete range of diesel performance products.