Cummins L9: Engine and engine cooling — manifold/header/muffler/tail pipe

Affects Cummins L9 · — — about 494 vehicles.

The hazard

Exposure to high levels of ammonia can increase the risk of injury.

What to do

Dealers will recalibrate the engine, free of charge. Owner notification letters were mailed August 20, 2021. Owners may contact Cummins customer service at 1-800-286-6467.

Critical — crash/injury risk now High — injury risk; see remedy Moderate — fix at next service Low — minor / informational