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May 28, 2026 Service bulletin

Customer Experience: Diesel Exhaust Fluid (DEF) gauge on the cluster is erratic or has fluctuations

Ram technical service bulletin 9100823 for 2025-2026 Ram 2500, 2025-2026 Ram 3500 and 2025-2026 Ram 5500 and others.

Bulletin number
9100823
Component
Unknown or other
Summary
Customer Experience: Diesel Exhaust Fluid (DEF) gauge on the cluster is erratic or has fluctuations. Gauge is displaying a level not representative of what is in the tank. In some cases the level drops below the low level warning and customers gets an EVIC warning. When DEF level is too low the vehicle will be derated to 5 mph after 200 miles of dropping below the low level warning. From MY13 to MY24, the DEF pump had the level sensor integrated into the pump, but this changed for MY25+. In MY25 and beyond the sensor is now welded to the DEF tank. Technicians are replacing DEF pumps for faulty level sensor concerns. Replacing the DEF pump will do nothing to improve issues with the DEF level gauge. DEF pumps being replaced for level sensor/gauge issues has now become one of the most significant warranty issues for the DEF system as a whole. DEF system Eng. team is currently working with Cummins (who owns the PCM) to properly filter the signal sent from the DEF level sensor in the tank, to prevent the erratic gauge readings.

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