If it’s got to have torque, it’s got to have a diesel engine. These powerplants have been around 1892, and only gotten better with time. Glow plugs, turbocharging, intercooling, DEF, and other advancements have come along to change the game every few years, but the core of it is as popular now as it ever was. So much so that it’s become common to see high-performance diesels hit up drag strips, or make cross-country trips hauling 20,000 pounds.
Of course, these demands can be a killer on drivetrains over time. PRW USA, a foremost expert on engine and drivetrain components, has pinpointed one potential failure point in the flexplates of diesel trucks, and in particular, the late model Ram trucks.
PRW found that from the factory, the Aisin six-speed automatic is already on the high end of its abilities, having to deal with up to 900 lb-ft of torque. The flexplate will develop hairline cracks that eventually snowball into larger cracks, and it’s not impossible to have the flexplate shatter at high speed and send pieces flying.
PRW’s solution is the PQx Signature Series flexplate. This flexplate meets the SFI 29.3 spec, which is used in diesel drag racing, and is made of one piece of billet steel, making it quite durable. It also features precise tolerances thanks to its CAD design, as well as a black oxide coating that will protect against oxidation. For a Cummins-powered racing application, the PQx Signature Series is the way to go.
Another solution is the PQx Platinum Series. This one meets the SFI 29.1 spec, which is more in line with street-going or towing applications. PRW makes the Platinum Series for several applications, including the 7.3/6.0/6.4-liter Power Strokes, as well as both Cummins (5.9/6.7-liter) engines. They feature a durable 4mm steel centerplate, and precision-welded starter ring gears.