The contact owns a 2016 Ford F-350. The contact stated that the check engine warning light was illuminated. The contact stated that after adding diesel particulate filter fluid in the vehicle, the message that the vehicle was low on fluid was displayed, and the vehicle would unintendedly decelerate to under 50 MPH. The vehicle was taken to the dealer, who replaced the DPF pump and burner. Approximately 30,000 miles later, the failure recurred, and the vehicle was returned to the dealer. The dealer replaced the DPF pump and burner again. The manufacturer was informed of the failure and opened a case. The manufacturer transferred the contact to the NHTSA Hotline to report the failure. The failure mileage was 52,860.