The current Class 8 long-haul tractors that make up the vast majority of the North American on-highway fleet, with their real engine, transmission, and sleeper options.
Freightliner
The best-selling Class 8 tractor in North America — the default fleet spec, with the widest parts and service network of any truck on the road.
Engine options
Detroit DD13 (370–525 hp) or DD15 (425–505 hp); Cummins X15N (400–500 hp)
Transmission
Detroit DT12 automated manual (12-speed)
Sleeper options
48", 60", 72" mid-roof; 60", 72" raised-roof
Typical GVWR
52,000–62,000 lb depending on spec
The Cascadia's biggest practical advantage for an owner-operator isn't a spec sheet number — it's resale liquidity and parts availability. Every truck stop and dealer network is built around it.
Peterbilt
Peterbilt's flagship long-haul tractor, known for strong resale value and the largest factory sleeper of any major OEM.
Engine options
PACCAR MX-13 (405–510 hp, 1,450–1,850 lb-ft)
Transmission
PACCAR TX-12 automated manual (12-speed)
Sleeper options
Up to 80" UltraLoft — the largest factory sleeper from any major OEM
Suspension
SmartAir rear suspension — automatically adjusts ride height/damping to load
The 579 and Kenworth T680 share the same PACCAR MX-13 engine and TX-12 transmission underneath — the real differences are cab layout, sleeper size, and brand-specific styling/resale patterns.
Kenworth
Kenworth's long-haul flagship, sharing PACCAR's MX-13/TX-12 powertrain with the Peterbilt 579 but with its own cab and a reputation for build quality.
Engine options
PACCAR MX-13 (405–510 hp, 1,450–1,850 lb-ft)
Transmission
PACCAR TX-12 automated manual (12-speed)
Sleeper options
76" sleeper — widely regarded for build quality and driver comfort
If you're cross-shopping the T680 against the Peterbilt 579, the powertrain decision is identical (same PACCAR engine/transmission) — the real choice is cab feel, sleeper size, and which brand's dealer network is closer to your operating area.
Volvo Trucks
Volvo's long-haul flagship, built around a tightly integrated Volvo-only powertrain and known for driver comfort and aerodynamic efficiency.
Engine options
Volvo D13 — variable-geometry turbo or turbo-compound, 405–455 hp, 1,450–1,850 lb-ft
Transmission
Volvo I-Shift automated manual — 12- or 13-speed (the only transmission offered behind the D13)
Sleeper options
Up to 74" high-rise/stand-up sleeper
Typical GVWR
~51,000 lb (varies by spec)
Volvo only pairs the D13 with its own I-Shift transmission — unlike Freightliner, Peterbilt, or Kenworth, you can't mix and match an outside transmission brand into a VNL.
Mack
Mack's on-highway flagship, built on the same heavy-duty durability reputation Mack built its name on in vocational and construction trucks.
Engine options
Mack MP7, MP8 (434–505 hp, 1,460–1,760 lb-ft), or MP8HE (415–445 hp, 1,760–1,860 lb-ft)
Transmission
Mack mDRIVE automated manual
The MP8HE ("High Efficiency") variant trades some peak horsepower for turbo-compounding and better fuel economy — worth comparing against the standard MP8 based on your actual duty cycle, not just the horsepower number.
International
International's long-haul flagship, built around the S13 Integrated Powertrain — a proprietary engine/transmission pairing engineered as one unit rather than separately sourced components.
Engine options
S13 Integrated Powertrain — up to 515 hp, 1,850 lb-ft (lightest 13-liter diesel in North America)
Transmission
T14 automated manual (14-speed, optimized for direct drive) — integrated with the S13
The S13's integrated design means the engine and transmission are tuned together as a single system rather than an engine bolted to a separately-sourced transmission — International's pitch is fewer calibration mismatches between the two.
Mechanically, almost nothing — they share the same PACCAR MX-13 engine and TX-12 transmission underneath. The real differences are cab design, sleeper size and layout, and brand-specific resale and dealer-network patterns in your operating area.
The Freightliner Cascadia and Peterbilt 579 are generally considered the strongest resale performers, largely because of how widely they're spec'd across fleets — more buyers looking for that truck means an easier, faster sale when you're ready to trade.
Both use tightly integrated, single-source powertrains (Volvo D13/I-Shift, International's S13 Integrated Powertrain) engineered as one unit — the pitch is fewer engine-transmission calibration mismatches. The tradeoff is less flexibility to mix and match engine/transmission brands the way you sometimes can with other OEMs.
Specs reflect common current factory options and can change by model year or region — always confirm exact figures against the manufacturer's current build sheet before making a purchase or maintenance decision.