Overview

Overview
This 2026 Peterbilt 579 conventional sleeper tractor is set up for general freight hauling, configured to pull a 53' van trailer. It rides on a 240" wheelbase with a 52,000 lb GVWR and is finished in white over a black frame.

Engine & Drivetrain
Powered by a Cummins X15 rated 450 HP @ 1700 RPM (governed at 1700), 1650 lb-ft @ 950 RPM, EFF Series 2024-emissions engine. Paired with an Eaton EEO-16F112C12 Endurant 12-speed automated transmission (no cooler), column-mounted RH shifter, economy shift calibration, and neutral coast mode at pedal only. Driveline consists of an RPL20 interaxle and RPL25 SD driveline with one midship bearing, running a 2.85 rear axle ratio. Equipped with a Jacobs compression brake, EMUX electronics architecture, predictive cruise control package, and adjustable/standard-following-distance adaptive cruise control. Effective VSL setting is 65.0 MPH or greater, with a typical operating speed of 65 MPH and powertrain optimized for fuel economy at 90%+ time near cruise speed. Safety systems include Bendix ESP electronic stability program with ATC (tractor service), Bendix Fusion Stop and Auto-Go Advanced, an RH side sensor for Bendix collision mitigation, a 6S6M anti-lock braking system, and tire pressure monitoring. Additional engine equipment includes a PACCAR 160-amp brushed alternator, PACCAR premium starter, three PACCAR premium 12V dual-purpose batteries (2190 CCA), low voltage disconnect system, Horton on/off fan clutch, 18.7 CFM aspirated air compressor, DAVCO 382 fuel/water separator with 12V heater, high-efficiency cooling system, single RH horizontal exhaust with under-cab DPF/SCR, an immersion-type block heater (110-120V), and synthetic axle lubricant on all axles. Global telematics hardware is installed with wiring provisions for both telematics and ELD (RP1226), plus a SmartLinq RD 5-year remote diagnostics subscription.

Chassis & Axles
Front axle is a Meritor MFS+12E rated 12,500 lbs with a 3.5" drop, taper leaf springs, greasable spring pins, Meritor Wide Track, and 30mm spring spacer blocks, riding on Bendix ADB22X-LT front disc brakes with Tenneco shocks. Power steering is a TRW THP60 with a frame-mounted reservoir. Rear axle is a PACCAR DX-40 rated 40,000 lbs (tandem drive) with Bendix ADB22X-LT rear disc brakes. Front and rear hubs are PHP10 aluminum Preset+ (air disc). GAWR front is rated 12,000 lbs with a 52,000 lb GVWR; GCW is rated 80,000 lbs. Frame consists of 10-5/8" steel rails (326"-384") at 5/16" thickness with aluminum crossmembers, a tapered EOF tractor design with kingpin cutout, and a maximum grade rating of 6%. Fifth wheel is a JOST JSK37 top plate on an inboard air slide mount (18" slide), with LH release and a 6.6"-7" mounting height. Dual aluminum fuel tanks include a 135-gallon tank RH behind cab and a 110-gallon tank LH behind cab, with dual shutoff valves, center fill, perforated anti-siphon devices, and a 20-gallon aero DEF tank mounted LH BOC (1:1 DEF-to-fuel ratio); the chassis is centrally fueled. Air system includes a Bendix AD-HF air dryer with heater and coalescing filter, steel painted air tanks, a self-returning dash-mounted brake hand valve, and a pneumatic park brake. Exterior equipment includes an aero aluminum battery box, molded 3-piece aero bumper, full chassis aero fairing package (LH/RH quarter fender to BOS with rubber skirts and EPIQ aero package to BOS), front tire closeouts, PolyArmor black quarter fenders with Peterbilt logo mudflaps, and a frame-mounted deck plate/access package on the LH side.

Suspension
Rear suspension is a PB Low Air Leaf rated 40,000 lbs with a 52" spread, built light-weight, with a dash-mounted dump switch and suspension indicator light.

Cab & Interior
Aero 124 BBC aluminum cab with a Metton hood and thermal insulation package. Interior is a Prestige trim in Sterling Gray with an 80" UltraLoft sleeper featuring a second bunk with ladder, coil spring mattress, walkthrough curtain, wardrobe cabinet shelves, thermal insulation, sleeper cabinet door and drawer package, a 1.8 ft³ refrigerator, RH baggage door, RH full-height access door with tilting window and RH sleeper side tilting window, provisions for a 22" flat-panel TV, 12V power outlet, USB port, and rear sleeper audio controls. Seating includes Peterbilt LX premium driver and passenger seats (air ride, high back) with RH/LH armrests. Features a multi-function steering wheel with integrated audio/cruise controls, tilt/telescoping column, one-piece curved windshield with privacy curtain, power door locks and power windows, vanity mirrors, and a D2 fuel-fired sleeper heater with digital controller alongside a combo fresh-air heater/air conditioner. Outside sunvisor is painted composite, and motorized, heated aero mirrors with integrated convex lenses are fitted along with black rectangular hood mirrors and an A-pillar fairing. Audio includes a ConcertClass AM/FM/WB radio with 3.5mm aux, satellite radio, Bluetooth phone/audio, dual USB charging, and a Cobra 29 CB radio with antenna. Instrumentation is a 15" digital cluster display showing engine oil temperature, air filter restriction pressure, brake application air pressure, suspension air pressure (load), engine hourmeter, manifold pressure (turbo boost), and engine percent torque. Additional equipment includes composite fender-mounted headlights with integral DRL/park/turn/side marker, five aero LED marker lights, daytime running lights, self-canceling turn signals, LED oval stop/turn/tail/backup lighting, two LED load lights, fuel provisions for an auxiliary power unit, a removable bugscreen, electric windshield wipers with intermittent feature, an auto-reset circuit protection system, a fire extinguisher, and a triangle reflector kit. Exterior is finished in a two-stage Axalta white (cab, hood, sleeper, fenders, bumper, and fairings) over a black frame.

Tires & Wheels
Front tires are Goodyear 16-ply 295/75R22.5 (RY023) mounted on Accuride 43644SP 22.5x8.25 aluminum wheels in standard polish. Rear tires are Goodyear 16-ply 295/75R22.5 (TY517 MC2) on matching Accuride aluminum wheels, standard polish, eight-tire rear configuration.

Warranty & Protection
Backed by the manufacturer's base emissions warranty of 5 years/100,000 miles (Cummins engines) and Peterbilt Class 8 standard coverage of 1 year/100,000 miles (160,000 km).