Cummins is delaying the launch of its 10-liter X10 and the new 7-liter B-Series engines, multiple dealers and OEMs have confirmed to CCJ.
For calendar year 2027, Cummins will continue offering the B6.7 engine, delaying the launch of the B7.2 until 2028. Since the B6.7 does not meet EPA27 emissions standards, Cummins plans to absorb the non-compliance fines and pass those costs through to the engine's pricing, sources told CCJ.
Production of the medium-duty and vocational B7.2 was originally set to kick off next year. The engine improves top-end performance ratings over the B6.7, providing 240 to 340 hp and 650 to 1,000 lb-ft of torque.
X10 delayed to mid-2027
Cummins also notified truck manufacturers that the X10 launch has been pushed to July 2027—about six months later than intended.
Production of the L9 and X12 engines will continue through the first half of 2027 the company told OEMs; however, since these models are also non-compliant with EPA27, Cummins will similarly pass the associated fine costs along, sources told CCJ.
The X10, an optional centerpiece of Mack's redesigned Granite, would add 70 additional horsepower and 400 foot-pounds of torque, and features an oil drain interval improvement of 25,000 miles versus the current L9.
The new engine, a replacement for Cummins's L9 and X12, is engineered to bridge multiple commercial vehicle tiers, positioning it to capture market share across a broader array of medium- and heavy-duty industrial applications. For heavy-duty applications, the X10 delivers up to 450 horsepower and 1,650 lb-ft of torque. For applications requiring a medium-duty package, the X10 delivers ratings up to 380 horsepower and 1,250 lb-ft of torque.
The Cummins X15 diesel, itself also originally delayed about six months, is still on pace to make its market debut for model year 2027.
Truck and engine manufacturers are just six months from having to meet tighter emissions limits that have not yet been fully finalized by the Environmental Protection Agency following regulatory upheaval that started last year.
Once EPA releases its proposed rule, Cummins told CCJ Tuesday afternoon, the company will review details with its OEM customers and suppliers "to continue assessing our product plan and implementation requirements."
"That review will take time," the company said. "We continue to move forward with a product plan focused on dependable solutions that deliver meaningful benefits."
