The 2010 Cummins ISX11.9

Claiming better fuel economy, better performance, and better reliability compared to today’s ISX, the Indiana engine-maker says the ISX15 features the Cummins XPI fuel system, an enhanced cooled-EGR system, and a single VGT variable-geometry turbocharger. The new Cummins aftertreatment system uses selective catalytic reduction (SCR) catalyst technology together with the in-house-made particulate filter that was introduced in 2007.

The XPI fuel system, co-developed with Sweden’s Scania, mates with a single overhead camshaft, whereas the ’07-spec ISX had two overhead cams. Ratings will be maintained from 400-600 hp, with torque outputs from 1450-2050 lb ft. Cummins claims an industry-leading power-to-weight ratio among big-bore engines. It also claims fuel economy gains of up to 5% compared to its own 2007 engines, and as much as a 9% advantage over International’s 2010 EGR engines.

The new ISX11.9 is a compact and lightweight medium-bore engine aimed at vocational trucks, day cabs, and emergency vehicles. Sharing the same cooled EGR, VGT Turbocharger, XPI fuel system, electronic controls and aftertreatment system seen on the ISX15, it will be offered with ratings from 310-425 hp and torque from 1150-1650 lb ft. 

The ISX15 will continue to feature the Intebrake, an integrated engine brake; and the ISX11.9 will be offered with an optional engine compression brake.

Steve Charlton, Cummins vice president, heavy-duty engineering, notes that these two ISX engines have a very large ‘sweet spot’ — due to the low-temperature nitrogen-oxide conversion capability of the copper-zeolite catalyst – making them “extraordinarily driver-friendly”. He adds that fuel economy gains can be realized by even the most inexperienced driver.

Cummins says its 2010 mid-range engines – the ISB6.7, ISC8.3 and ISL9 — are “nearly identical” to their 2007 counterparts with the addition of an SCR catalyst in the aftertreatment system. The biggest change for 2010 is that these engines will share a common Electronic Control Module (ECM) with their heavy-duty big brothers. It has more input/output and processing capability for full integration of the Cummins engine and aftertreatment system. 

Ratings go like this: the ISB6.7 offers 200 to 325 hp with peak torque of 520-750 lb ft; the ISC8.3 will have truck ratings of 260-350 hp  with peak torque of 660-1000 lb ft; and the ISL9 will come with truck ratings of 345-380 hp and peak torque of 1150-1300 lb ft.