2020 Peterbilt 579 LD677335 357K mi. EPU installed

The Model 579’s features are the direct result of our customers’ input. We’ve considered the feedback of over 100 user tests and interviews with drivers, techs, and safety and maintenance managers in applications including over-the-road sleepers, LTL day cabs and vocational applications such as tankers and aggregate haulers.

The results add up to many technological advancements and a distinctively styled, super comfortable, sleeker, more aerodynamically and fuel-efficient Model 579. One that endured million-mile endurance tests and extensive field validation. No wonder it’s the most technologically advanced, fuel-efficient Peterbilt – ever.

• The PACCAR powertrain offers an integrated solution for maximizing MPG and payload capacity
• It combines durable PACCAR MX engines and DX-40k tandem drive axles
• The integration of these components allows for effortless pulling, improved efficiency, enhanced fuel economy and increased driver comfort
• The PACCAR MX-13, PACCAR MX-11 and PACCAR PX-9 engines utilize a combination of proven technologies and state-of-the-art innovations
• These engines are designed to maximize MPG and achieve the lowest possible fuel consumption, emissions and noise levels
• They incorporate variable speed engine components and optimized combustion
• PACCAR MX engines deliver exceptional reliability and proven performance, whether in linehaul or vocational heavy-duty truck applications

Other powertrain highlights include:

• Gear ratio coverage for slow-speed maneuvering
• High-performance thru-shaft pinion design that transfers full engine power straight to the road
• Fuel system efficiently optimizes combustion and decreases noise
• Broad torque curve that delivers up to 1,850 lb.-ft. and peak torque at low rounds per minute (RPM)
• Long-life maintenance intervals

The new PACCAR TX-12 PRO automated transmission is designed to be versatile and efficient, while also remaining tough and durable. It is engineered to operate with engines that have up to 1,000 lbs.-ft. of torque and a maximum Gross Combination Weight Rating (GCWR) of 70,000 lbs.

More TX-12 Pro Features and Benefits include:

• Dual PTO functionality to power multiple hydraulic devices simultaneously
• New Extreme Duty Clutch for improved low-speed maneuvering with higher loads
• Rock Free Mode helps rock the truck free from mud, sand or snow
• Off-Highway Calibration enables shift points that are tuned for changing off-highway conditions with a bias toward shifting less often
• Secondary Configuration for a tailored driving experience that accounts for toggling between two calibrations for the load or terrain