Cummins X15

14.9 litre2017 to presentGHG17 (2017)

The volume choice in North American linehaul, sold in Efficiency and Performance series that are the same iron with different tuning and different ratings. Efficiency is aimed at fleets running tall gears at 62 to 65 mph; Performance is for heavy haul and hills.

Output

400-605 hp

1450-2050 lb-ft peak torque

Fuel per mile

$0.551

at 7.3 mpg and $4.049 a gallon

Fuel a year

$66,106

over 120,000 miles

In-frame overhaul

$22k-$32k

rough, and shop rates move it

In the exhaust

DPF and SCR, single canister

The first greenhouse gas phase targets the whole vehicle rather than the engine, so this era is as much about aerodynamics, tyres and axle ratios as combustion. Downspeeding becomes standard: tall gears, low cruise revs.

Known issues

Aftertreatment rather than the engine: DEF dosing units, NOx sensors and the occasional turbo actuator. The bottom end is not the problem and rarely is.

Verdict

If you buy a modern aerodynamic tractor you are probably buying this engine, and it is a sound one. Budget for aftertreatment sensors as a running cost rather than an event.