Your emissions system is only as reliable as its sensing and control points—and few are more crucial than the DEF (Diesel Exhaust Fluid) head unit. For REV Group trucks powered by the Cummins ISL engine, the REV PARTS LLC Cummins ISL DEF Head Unit, OEM 10344986, is designed to keep your aftertreatment system running accurately. When this module fails or drifts, your vehicle may encounter errors, derates, or emissions compliance issues right when you least expect them.
-
Monitors DEF fluid level, temperature, and urea concentration, relaying that data precisely to the engine control module
-
Regulates accurate dosing of DEF into the exhaust stream, enabling the SCR (Selective Catalytic Reduction) system to reduce NOx emissions efficiently
-
Built to match OEM 10344986 tolerances, ensuring a direct-fit replacement for REV / Cummins ISL systems
-
Helps prevent fault codes, check engine warnings, and engine derates caused by faulty or drifting sensor feedback
-
Designed to withstand harsh conditions—vibration, temperature cycling, and exposure to DEF chemistry
-
Field-replaceable design assists in minimizing vehicle downtime
Don’t let a failing DEF head unit become the weak link in your emissions setup. Installing the correct OEM 10344986 REV PARTS LLC Cummins ISL DEF Head Unit restores accuracy to your emissions feedback loop, keeps your SCR system functioning properly, and protects your vehicle from surprise faults or derates. In clean engine operation, every sensor counts—and this one counts a lot.























































































































































































































































































