Cummins Looking Into Ram HD Engine Emissions Certification Process

Cummins, maker of the beastly 6.7-liter inline-six diesels found beneath the hoods of various Ram Heavy Duty pickups, claims it is looking into its emissions certification and compliance process.

In a statement released Monday, the decision to investigate the process came after “conversations” with the Environmental Protection Agency and California Air Resources Board. Specifically, the probe targets the revamped engines used in Ram’s 2019 HD line, not the 5.0-liter V8 found in the Nissan Titan XD.

“This review is being conducted with external advisors to ensure the certification process for Cummins pickup truck applications is consistent with its internal policies, engineering standards and applicable laws,” the company said. “Cummins has voluntarily disclosed the review to our regulators and other agencies and will cooperate with them to ensure a complete and thorough review and implement recommendations for improvement.”

For 2019, the Ram HD buyer has a choice of two Cummins flavors: a 370 horsepower, 850 lb-ft mill available in the Ram 2500 and 3500, and a class-leading 400 hp, 1,000 lb-ft variant available only in the 3500 (when equipped with Aisin automatic transmission).

Numerous changes separate the new 6.7L mills from their predecessors. Among them, a compacted graphite iron block that drops weight by 60 pounds, a new cast-iron cylinder head (featuring high-temperature exhaust valves actuated by in-block hydraulic lash adjusters), a new fuel delivery system, and new connecting rods, bearings, and crankshaft.

While neither Cummins nor Fiat Chrysler has elaborated on the probe, it brings to mind the recent investigation launched by Ford into how the company determines road load specifications for the fuel economy and emissions certification process. Ford now finds itself subject to a Justice Department probe.

“We are reviewing our certification process and it’s too early to tell what, if any actions, would or might be needed,” Jon Mills, a Cummins spokesman, told Bloomberg.

When contacted by the publication, an FCA spokesperson said the automaker is happy to cooperate as needed.

Ram’s 2019 HD line went on sale this month, with the upgraded turbo-diesel powerplants serving as a standout feature FCA hopes to beat its competitors over the head with. Execs no doubt hope the probe turns up zilch. The EcoDiesel fiasco is still too close in the rear-view.

[Images: © 2019 Matthew Guy/TTAC, Cummins]