Peterbilt unveils new Class 5-8 medium-duty trucks, PACCAR TX-8 transmission

Peterbilt unveils new Class 5-8 medium-duty trucks, PACCAR TX-8 transmission

Peterbilt Motors Co. has unveiled the new medium-duty Model 537 and Model 548, designed for the Class 7/8 segment, as well as the medium-duty Model 535 and Model 536, designed for the Class 5/6 non-CDL lease and rental markets.

Each new model is available for order with deliveries starting in July.

Model 537 and Model 548

Peterbilt says the new Model 537 and Model 548 is built upon a brand-new customizable chassis and robust multiplex electrical architecture. The trucks deliver seamless body builder integration, according to the OEM.

The trucks have two hood options, a vocational three-piece Metton hood featuring a stationary grille with full through rail, and a three-piece SMC aero hood for maximum visibility. Both hood options can use a variety of vocational and FEPTO bumpers to fit different applications. The bumper is front-mounted to the chassis with a drop-and-go feature for self-locating. Bumper options include two finishes (chrome or painted), three bumper light mounted options (headlight, daytime running lights or fog), two radar options, two tow options (two tow loops or center tow), and two license plate mounting locations (center or offset).

The new Model 537 and Model 548 are available with wide or standard track axles featuring what the company says are superior wheel cut angles for a shorter turning radius and mono-leaf or taper-leaf front springs rated from 8,000 up to 20,000 lb. The rear suspension is available with a taper-leaf or air leaf suspension rated from 12,500 to 40,000 lb. depending on a single or tandem drive configuration. The AWD option features a new offset bowl design to offer the lowest possible cab height.

The new 2.1m cab is 8 in. wider inside than the previous generation cab and has room for 3 adults to seat comfortably, Peterbilt says. Stair-style steps and knurled grab handles make getting into the trucks easy. The interior features 4.6 cu.-ft. of storage space, three cup holders and a dash layout with available space for optional gauges, switches and ram mounts.

A new instrument cluster, featuring an analog speedo and tachometer with a high-resolution, 7-in. digital display relays key information at a glance. Drivers are able to toggle through menu cards on the digital display utilizing the new multi-function steering wheel and the display navigation knob. The digital display is deeply integrated into the electronics of the truck with key information like system check, trip summary, PTO functions, ADAS and TPMS all clearly displayed through the menu cards.

Model 535 and Model 536

The Model 535 and Model 536 trucks feature an aluminum cab with a width of 2.1 m, a floor height of 40.5 in. and a roof height of 74 in. The cab is 8 in. wider than the previous generation cab and has room for three adults to seat comfortably. Ingress and egress is improved with a 3-in. lower cab height, stair-style steps and knurled grab handles. The new, self-closing doors feature larger windows for increased driver visibility, three opening positions and a new triple seal for enhanced NVH. The Bumper to Back of Cab (BBC) measurement can be either 107 in. or 109 in. and the trucks offer a turning radius of 51 ft.

Options available on the Model 535 and Model 536 include two hood lengths, two roof heights, composite and steel bumpers, as well as multiple options of fuel and DEF tanks.

The cab interior has fit and finish with high or low-back seats in cloth or vinyl. The trucks have three cup holders and 4.6 cu.-ft. of overhead and door storage space. The dash layout of the Model 535 and Model 536 is fully customizable for any application with available space for optional gauges, switches and ram mounts, the company says.

Driver information is delivered through a new instrument cluster, featuring an analog speedo and tachometer and a high-resolution 7-in. digital display. The 7-in. display relays key information at a glance thanks to a menu card layout. Drivers are able to toggle through pre-loaded menu cards and customize their preferences utilizing the new multi-function steering wheel and the display navigation knob. The digital display is fully integrated with the ADAS system on the truck (collision mitigation, lane departure warning) as well as the TPMS system. Other functions include a system check and trip summary.

PACCAR TX-8 transmission

Alongside the new medium-duty Model 535, Model 536, Model 537 and Model 548, Peterbilt unveiled the new PACCAR TX-8 automatic transmission and updated PACCAR PX engines.

The new 8-speed PACCAR TX-8 automatic transmission monitors changes in road grade, vehicle acceleration, torque demand, weight and engine load to keep the truck in the most fuel-efficient gear, Peterbilt says, adding its shift performance delivers up to 5% better fuel economy.

The company says the PACCAR TX-8 automatic transmission features the Auto Park Lock system, a safety feature that automatically engages the park lock should a driver forget. A Twin Torsional Damper enables early 1st gear lock-up for smoother shifts and faster acceleration. Also, the Mechatronic unit and Transmission Control Unit (TCU) are combined into one unit within the oil pan for ease of service.

Peterbilt says the transmission features a new, service-friendly design which eliminates several integrated and external parts.

Peterbilt’s new family of medium-duty trucks is equipped with PACCAR’s updated line of PX engines. The updated PX-9 also sees higher torque ratings in the 260, 350 and 360 HP versions as well as a lower torque drop-off speed.

In addition to the launch of the new PACCAR TX-8 automatic transmission and updated PACCAR PX engines, existing PACCAR powertrain components will be rebranded to align with the newest member of the family. All PACCAR transmissions will take on the TX designation with the 12-speed being renamed the TX-12. The PACCAR 40K drive axle will become the PACCAR DX-40 and the vocational 20K front steer axle becomes the FX-20.

On the heels of the next-gen Peterbilt Model 579

The new medium-duty announcement comes just months after Peterbilt unveiled its next-generation Peterbilt Model 579 Class 8 on-highway truck. If you missed that announcement, you can find it here:

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