Def derate

[jack4540]

Has anyone else experience a def derate on their frieghtliner with the cummins engine

[Martigg]

2018.5 Seneca (S2RV Chassis)-DEF light & check engine light came on w/3 DEF squares lit. As instructed by Freightliner pulled into Odessa Freightliner & “DEF Header” was replaced. They had part in stock & mechanic said it was a common problem. Drove it 150 mi. when this occurred never did go to derate. Drove several thousand miles after DEF Header was replaced. No problem.

[Drv]

Pretty Good discussion in this Link.
Mine is going in soon to check hose routing and check of Def Header.
Hope this helps!
https://www.jaycoowners.com/forums/f...des-78302.html

[jack4540]

Thanks