Cummins Recalls L9 Diesel Engines Due to Excessive Ammonia Exhaust
Cummins is recalling specific L9 Diesel Engines because software calibration may allow excessive ammonia into the tailpipe, increasing injury risk.
What this means for you
Our assessment, not the agency’s: severity 3/5 (High).
Real risk of harm even if no illness or injury has been reported yet. Stop using the product and follow the agency's guidance.
Our severity reasoning: The recall involves a risk-of-harm product (excessive ammonia exposure) where injury has not yet been reported, fitting the criteria for a High severity score.
Plain-English summary
Cummins, Inc. is recalling certain L9 Diesel Engines with part number D563027BX03. The recall addresses a defect in the engine calibration software, which may allow excessive ammonia to enter the tailpipe exhaust during the management of Diesel Exhaust Fluid injection.
Exposure to high levels of ammonia can increase the risk of injury. The source text does not specify the number of affected vehicles or report any specific injuries or illnesses.
Dealers will recalibrate the engine free of charge. Owner notification letters were mailed on August 20, 2021. Owners may contact Cummins customer service at 1-800-286-6467 or the NHTSA Vehicle Safety Hotline at 1-888-327-4236.
The recalled product
- Product
- ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:MANIFOLD/HEADER/MUFFLER/TAIL PIPE recall
- Manufacturer
- Cummins, Inc.
- Category
- Vehicle — Engine Component
- Hazard
- Affected units
- 494
Distribution
Distributed nationwide across the United States.
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