Driving Paccar’s TX-18 Transmission: An Iron Fist in a Velvet Glove
Paccar Automated Transmissions Available in Medium-Duty Peterbilts
Peterbilt said its medium-duty Models 548, 537, and 536 with Pacaar PX-9 engines will be available with Paccar TX-12 and TX-12 Pro automated transmissions.

Two automated transmissions, the Paccar TX-12 and TX-12 Pro, are available in Peterbilt Models 548, 537, and 536.
Photo: Peterbilt/Work Truck
Peterbilt said Paccar TX-12 automated transmissions with Paccar PX-9 engines will be available for medium-duty Models 548, 537, and 536. Both the standard Paccar TX-12 and TX-12 Pro versions seamlessly integrate with the PX-9, offering efficient operation and superior drivability.
“Together, the TX-12 transmissions and PX-9 engine, create an exceptional combination of efficiency and reliability,” said Jake Montero, assistant general manager, sales and marketing for Peterbilt. “Our medium-duty customers can spec confidently knowing this new powertrain configuration delivers increased productivity and an excellent driving experience.”
Paccar TX-12 Efficient for On-Highway Tasks
Designed to be one of the most efficient on-highway transmissions, the TX-12 features lightweight and robust construction. Combined with the PX-9 engine, it operates up to 1,250 lbs.-ft. of torque with a maximum gross combination weight rating (GCWR) of 66,000 pounds for pick-up and delivery and other tractor applications.
Paccar TX-12 Pro Ready for Rugged Work
The TX-12 Pro builds on the TX-12 foundation with increased versatility and efficiency for more rugged applications. Operating with the PX-9 engine, the TX-12 Pro supports up to 1,250 lbs.-ft. of torque and a maximum gross combination weight rating (GCWR) of 66,000 pounds supporting vocational applications such as snowplows, cranes, bucket/boom trucks, and more.
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