19-24 Ram 2500/3500/4500/5500 6.7L Cummins Walker Nitrogen Oxide (Nox) Sensor

Fits: 2019-2024 Ram 2500/3500/4500/5500 6.7L Cummins

It’s a NOx (nitrogen oxide) sensor designed for use on diesel engines with approximate emission-aftertreatment systems (e.g., SCR) where monitoring NOx in the exhaust gas is required. If your truck’s ECM logs fault codes related to NOx sensor readings, SCR system errors, or if the aftertreatment system isn’t functioning properly. If the sensor itself is damaged (due to extreme heat, contamination, wiring issues) or becomes inaccurate over time.

In vehicle service bulletins or maintenance intervals suggesting replacement due to emissions compliance or sensor failure.

Use the correct sensor location: NOx sensors often have specific upstream/downstream positions relative to the SCR catalyst. Installing in the wrong bung could mislead the ECM. Ensure the harness connector is clean, corrosion-free, and the wiring integrity is good (often these sensors are exposed to heat, soot, vibration).

Ensure any stock gasket or seal (if applicable) is in good condition and re-torque to spec—exhaust leaks around the sensor location can cause erroneous readings. Because this sensor sees hot and possibly corrosive exhaust environment, when reinstalling ensure threads are clean, possibly apply anti-seize if the OEM recommends (but check instructions). After replacement, clear fault codes and monitor system performance (SCR regen, NOx levels, etc) to verify proper function.

Mopar: 285-1127