Peterbilt 379 vs Kenworth W900: Differences and Which to Buy

Same Parent, Different Houses

Pacific Car and Foundry, the company now called PACCAR, bought Kenworth in 1945 as its first big step into heavy trucks, then bought Peterbilt in June 1958. The two brands have been sister companies ever since, but they were never merged into one truck. Peterbilt built the 379 in Denton, Texas, while Wikipedia lists the W900's assembly in Renton, Washington, and Chillicothe, Ohio.

The timelines line up only partly. The W900 name goes back to the early 1960s, and the version most people mean in this debate is the W900B, introduced in 1982 with rectangular headlamps, and the W900L, which arrived in 1990 with about 10 more inches of hood. The Peterbilt 379 came along for 1987 and was retired in 2007, replaced by the 389. Wikipedia's W900 article names the 379 as the W900L's direct competitor. The Kenworth simply kept going: the company announced in March 2025 that W900 production would end in 2026.

Cab and Hood: Aluminum vs Fiberglass

Peterbilt's cab story starts in 1945, when, according to the company's history as summarized by Wikipedia, it introduced lighter aluminum-built cabs to raise payloads. The 379 carried that habit forward with an aluminum hood shell, still sold as a replacement part for both the 119-inch and 127-inch versions. Ask a 379 owner what makes the truck special and the aluminum hood usually comes up.

Kenworth went its own way up front. The W900 uses a forward-tilting hood, and Smart-trucking.com, an enthusiast site, describes the W900B hood as fiberglass and heavy to tilt. Truck News says the W900B brought aluminum construction, refined aerodynamics and an upgraded suspension to make the truck lighter and more fuel-efficient. Hood length differs too: Wikipedia lists the 379 at 119 inches or, extended, 127 inches bumper to back of cab, while a Kenworth dealer gives the W900L's BBC as 130 inches.

How to Tell Them Apart

Start with the badge, because the shapes are close. Peterbilt has used its red oval emblem since 1953, and a bird-style hood ornament has ridden on its conventionals since 1965. Kenworth's emblem is the "bug," the stylized KW whose letters come from Harry Kent and Edgar Worthington, the two men whose names formed the company name in 1923.

Next, the headlamps. The 379 made rectangular lamps standard and moved the turn signals up into the headlamp housing. The W900B also wears rectangular lamps, so lamp shape alone will not settle it; look at the badge, the grille surround and the hood's proportions instead. On a W900L, the extra length shows in how far the nose runs ahead of the cab. Remember that both trucks are favorites for customizing, so a show truck may wear aftermarket hoods, lamps and visors that blur the factory differences.

Engines and the Ride

Under the hood, the two shared the same supplier list for years. Wikipedia lists the 379 with Caterpillar's 3406 family through the C15 and C16, Cummins' NTC, N14, ISM, ISX and Signature 600, and the Detroit Diesel Series 60. The W900 menu, by the same source, runs from Caterpillar's 3406, 3408, C11, C13, C15 and C16 to Cummins' N, K, M and ISX series, Detroit's 71, 92 and 60 series, and later PACCAR's own MX engines. The difference is time. The 379 retired before PACCAR's MX engines reached it, while the W900 lived on, and a Kenworth dealer lists today's W900L with the PACCAR MX-13 or Cummins X15 at up to 605 horsepower.

Ride and interior are where the forum wars live, with drivers arguing over legroom, dash layout and cab noise. Ritchie Bros.' comparison describes Kenworth cabs as quiet and practical and Peterbilt as known for premium interiors and fit and finish. Treat all of that as opinion, not test data.

Resale and Collector Value

Peterbilt's long-hoods have a reputation for holding value. Ritchie Bros. says Peterbilt carries a resale premium in many markets and that the 389's strength mirrors that of the 379, while adding that the W900 also performs well, especially with low mileage and desirable specs. No major collector price guide tracks either truck, so asking prices are just that.

Numbers point to the special editions. FleetOwner reported that Peterbilt built more than 230,000 Model 379s starting in 1986, and the final 1,000 were badged Legacy Class 379s with numbered dash plates. Kenworth says more than 280,000 W900s have hit the road and is closing the run with the W900 Legacy Edition, 1,000 serialized trucks. For a buyer, that leaves a simple split: a 379 is a finished chapter with an aluminum hood and a big supply of used trucks, and a W900L can still be found nearly new, at least until the last 2026 builds are gone.