Cummins, Detroit, PACCAR, or a legendary CAT? A plain-English guide to the engines under the hoods in our inventory.
The engine defines a truck’s character — its power, fuel economy, service costs, and resale. Here’s a quick guide to the ones you’ll see most.
Cummins X15
The industry workhorse. Huge parts and service network, strong power, and a reputation for going the distance. Available in performance and efficiency tunes.
Detroit DD15
The default in Freightliner Cascadias. Excellent fuel economy paired with the DT12 automated transmission, and a mature aftertreatment system on newer years.
PACCAR MX-13
Found in Kenworth and Peterbilt. Lighter than some rivals, efficient, and increasingly popular with fleets running the T680 and 579.
The legendary CATs (C15 / 3406E / 6NZ)
CAT stopped building on-highway engines years ago, which is exactly why pre-emissions CATs command a premium. Mechanically simple, tunable, and beloved by owner-operators. A clean 6NZ C15 is collector-grade iron.
Filter our inventory by engine or ask us — we’ll match the powerplant to your routes and budget.