Exhaust System Emission Control Urea Injection System (def) Problems of Ford F-350

Ford F-350 owners have reported 2 problems related to exhaust system emission control urea injection system (def) (under the engine and engine cooling category). The most recently reported issues are listed below. Also please check out the statistics and reliability analysis of Ford F-350 based on all problems reported for the F-350.

1 Exhaust System Emission Control Urea Injection System (def) problem of the 2021 Ford F-350

Failure Date: 02/13/2026

The contact owns a 2021 Ford F-350. The contact stated that while operating the vehicle, the check engine warning light remained illuminated. The vehicle was taken to the local dealer who diagnosed that the def pump, def pump lines needed, and def heater element needed to be replaced. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was 92,567.

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2 Exhaust System Emission Control Urea Injection System (def) problem of the 2025 Ford F-350

Failure Date: 05/09/2025

The contact owns a 2025 Ford F-350sd. The contact stated that while operating the vehicle, the message "499 miles remaining of def" was displayed. The contact indicated that the message was displayed even though the def was 75% full. The failure had occurred on several occasions. The vehicle was taken back to the local dealer who was unable to determine the cause of the failure. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was 100.

See all problems of the 2025 Ford F-350 🔎.




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