By: Jack Roberts
Paccar — the parent company of Kenworth and Peterbilt — recently unveiled its TX-18 automated manual transmission (AMT) family — a new vocational design for on-and-off-highway applications based on the OEM’s TX-8 medium-duty, and TX-12 heavy-duty transmissions. Once again, the new AMTs are optimized for Paccar’s MX series of diesel engines.
The new TX-18 gearbox is optimized for on-highway, high-performance, and mild vocational applications, with the new TX-18 Pro version engineered for on-and-off-highway work in mild to severe applications.
The new transmissions will be available beginning in July 2022 for the following Models:
“These new transmissions are based on the Paccar TX-8 and TX-12 transmissions, which are getting great reviews for their passenger car-like performance and feel,” Kyle Crawford vocational product manager for Peterbilt, said during the official launch of the new transmissions earlier this year. “The TX-18 is designed for heavy-duty applications, with both versions rated up to 140,000 lbs. GCWR. So, it’s designed for heavy-duty applications like off-highway construction, heavy-duty wreckers and fleets that haul in mountainous terrain and need a little more power and performance to deal with those conditions.”
Crawford said features on the new AMTs include an extreme duty clutch, an 1,850 lb-ft torque rating and six reverse gears for the extreme duty TX-18 unit. “Those six reverse gears on the TX-18 are combined with a standard dual power-takeoff (PTO),” he added. “The PTO provides 75- to 160-horsepower and can be operated while driving. So, when combined with the TX-18’s six reverse gears, makes it an excellent choice for rock-spreading applications.”
Additionally, Crawford said, the TX-18 design features a 47% reduction in parasitic losses, and is 225 lbs. lighter than competitive AMTs on the market. It also features predictive cruise control, is fully integrated with current Paccar powertrain technology and systems, and can be programmed with four different application-specific calibrations to ensure peak performance in difficult applications.
Other important vocational features listed by Crawford include:
- An integrated clutch housing
- A transmission cooler option for GCWR ratings under 110,000 lbs.
- Internal wiring and sensors for added protection from the elements and enhanced uptime
- A standard oil temperature sensor
Another important feature Crawford pointed out is the TX-18’s “optimal” clutch engagement for hill-starts – even with 160,000 lbs. on a flatbed behind the truck. “The AMT automatically holds the truck still when the brake is released, and then selects the best gear possible to start and gain speed going uphill,” he explained. “The transmission will also automatically select the proper gear for holding the truck at a steady speed on down grades. This is a big benefit from a safety standpoint, while helping reduce driver fatigue. It also helps expand a fleet’s potential driver pool by making good drivers even better in difficult terrain conditions.”
