The Peterbilt 579 has been one of the most recognizable aerodynamic tractors on North American highways since its debut for the 2013 model year. In 2022 the model received its most significant update so far, and the changes went far deeper than a styling refresh. For owners, technicians and fleet managers, the redesign matters in a very practical way: many exterior and front-end components no longer interchange between the two generations. Understanding what changed, which parts are generation-specific and how to identify the right component saves time, freight costs and downtime.
This guide walks through the key differences, the part groups that deserve the most attention on the new truck and the simple checks that make ordering replacements accurate the first time.
What Changed With the 2022 Peterbilt 579
The second-generation 579 opened for orders in early 2022 and entered production that spring. Peterbilt designed it around efficiency and driver comfort, claiming up to a 7 percent fuel economy gain over the previous version on a like-for-like specification. Much of that gain comes from the bodywork, which is exactly where most replacement parts live. The main exterior changes include:
- A narrower, stronger hood made from Metton, a durable composite engineered to resist damage.
- A three-piece front bumper with an integrated cover for the forward collision radar and a larger aerodynamic air dam.
- Optional LED headlights with heating elements that keep the lenses clear of ice and snow.
- Redesigned chassis fairings, side skirts, closeouts and aero mirrors, plus optional rear fairings.
- A revised A-pillar vane that guides air around the windshield and helps cut cabin noise by about 10 percent.
Because the hood, bumper, headlights, grille and fairings all changed shape, a part designed for a 2013–2021 truck will not bolt onto a 2022 or newer model, and the reverse is also true. The interior was updated as well, with a 15-inch digital instrument display and a camera-based vision system, but body and front-end parts are where generation mix-ups happen most often.
Key Part Groups on the New-Generation 579
Most repairs and upgrades on the current 579 fall into six groups: the bumper, lighting, grilles and guards, aerodynamic body panels, mirrors, and cooling components. Each has its own design details worth knowing before you order.
The Three-Piece Bumper
The modular bumper is one of the most owner-friendly features of the redesign. Instead of a single large shell, it consists of a center section and two end extensions, backed by inner reinforcements and sealed with dedicated bumper seals. A complete assembly can include around nine individual pieces. The advantage becomes clear after minor contact: a scraped corner or a cracked extension can be replaced on its own, which keeps repair costs well below the price of a full bumper.
When ordering, note whether the truck has fog light openings, since bumper sections are produced both with and without fog holes. The center section also carries the radar cover, so any replacement must keep the sensor area clean, unobstructed and correctly aligned. After bumper work, it is good practice to have the collision mitigation system checked to confirm that the radar reads correctly.
Headlights and Fog Lights
LED headlights became a signature element of the new 579. They draw less power than halogen units, last far longer and produce a whiter beam that noticeably improves night visibility. Quality replacement assemblies should carry DOT compliance markings. On the new generation, fog lights are usually sold per side, so a single damaged lamp does not require buying a pair. Headlight assemblies for the two generations differ in shape and mounting points, so the model year must be confirmed before ordering.
Grilles and Grille Guards
The 2022+ grille has its own profile and comes with a bug screen that protects the radiator and charge air cooler from insects, gravel and road debris. For trucks running rural routes, a grille guard adds a solid layer of protection against animal strikes and can turn a potential tow into a minor cosmetic repair. Guards attach through model-specific brackets, and on the new 579 those brackets are designed around the three-piece bumper and the radar location. Choosing a guard and bracket set made for this generation keeps the frame mounting secure and the sensor field clear.
Fairings, Steps and Side Panels
Aerodynamic body parts take the most everyday abuse. Front step side panels carry upper and lower metal steps and absorb boot traffic, curb strikes and stone chips. Rear side panels and lower sleeper fairing extenders, often made of aluminum, close the gap between the cab and chassis to keep airflow smooth. Smaller support pieces, such as the sleeper extender brace, hold these panels in place and are worth replacing whenever a panel is reinstalled after damage. Some panels also changed during the generation itself, with certain rear side panels specific to 2023 and later trucks, which is one more reason to verify the exact build date.
Aero Mirrors
The redesigned aero mirrors are shaped to reduce drag and wind noise while giving the driver a wide, stable field of view. Mirror heads, glass and arm covers are exposed to branches, loading docks and wash-bay brushes, so they are among the most frequently replaced items on any long-haul tractor. When a mirror starts to vibrate at highway speed, check the mounting fasteners and arm joints before replacing the glass, because a loose mount will make even new glass shake. On trucks equipped with the camera-based vision system, confirm that a replacement mirror or bracket does not block any camera’s line of sight.
Cooling and Engine-Adjacent Components
The new 579 uses its own radiator packaging, water pumps and side air intake grilles. Radiator fins gather debris over high-mileage operation, so periodic cleaning from the engine side outward helps maintain cooling performance during long summer climbs. A water pump that shows weeping at the seal should be replaced before it fails completely, and it makes sense to inspect hoses and clamps at the same time, since these components age together.
How to Identify the Right Parts for Any Peterbilt
Peterbilt has built a wide range of models over the years, from classic long-hood trucks such as the 379 and 389 to aerodynamic platforms such as the 387, 587 and 579. Whether you are looking for parts for Peterbilt trucks from the classic long-hood era or the latest aero generation, the same identification steps apply:
- Check the tenth character of the VIN, which encodes the model year, and the build date on the door jamb label.
- Confirm the generation: for the 579, the split between 2013–2021 and 2022+ trucks affects almost every exterior part.
- Note configuration details, including fog light openings, radar equipment, sleeper type and fairing package.
- Record the side correctly: in North America, driver side means left and passenger side means right.
- Look for a part number printed or stamped on the old component and use it to cross-reference the replacement.
Catalogs organized by model and year make this process much easier. On tacoma-truckparts.com, for example, the newer 579 is listed separately from the 2013–2021 version, so parts for each generation stay clearly divided. A clear photo of the damaged part and its mounting points also helps confirm fitment quickly when a configuration is unusual.
Choosing Aftermarket Parts for the New Generation
Aftermarket components have become a popular choice for keeping newer trucks on the road, especially for body and front-end repairs. Well-made aftermarket parts for the 2022 Peterbilt 579 are produced to match factory dimensions and mounting points, so they install with the existing hardware. Body panels are typically molded from durable, impact-resistant polymers or reinforced materials, grille guards are made from steel, and lighting is built to meet DOT requirements.
A few details help compare options. Check whether brackets, seals and fasteners are included or sold separately. Decide whether a single side or a matched set makes more sense; replacing both fog lights or both sides of a fairing at once keeps color and finish consistent. For lighting, compare beam pattern, light output and housing finish, since black housings and chrome accents noticeably change the look of the truck.
Maintenance Habits That Protect the Front End
A few simple routines extend the life of the new 579’s body parts. Clean the radar cover during every pre-trip inspection, because road grime and packed snow can trigger sensor warnings. Inspect the bumper seals and air dam after winter driving or contact with snow berms. Check the fasteners on step panels and fairings periodically, since constant vibration can loosen them over time. Wash the bug screen and radiator face at regular service intervals to keep airflow strong in hot weather. Keeping a simple log of the part numbers you replace also makes every future order faster and more accurate.
The 2022 Peterbilt 579 is a more efficient, quieter and more serviceable truck than ever, and its modular design makes many repairs faster and more affordable. With a clear understanding of the generation differences and a habit of checking the VIN, build date and configuration before ordering, owners can keep this tractor looking sharp and earning reliably for many years.
Matthew Wilde
Matthew Wilde is an automotive journalist with experience contributing to leading publications. He focuses on delivering clear, well-researched analysis of automotive industry news and vehicles. Growing up surrounded by a variety of cars, Matthew developed a strong foundation in automotive technology and design. His work emphasizes accuracy and depth, aimed at informing both enthusiasts and industry professionals with straightforward, precise reporting.
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