Freightliner Cascadia 2017–2021 — technical service bulletin
Bulletin SB49-041 · NHTSA communication 10175414 · issued May 22, 2020
Technical service bulletin
communication type
Engine and Engine Cooling
component
2017–2021
model years
5
vehicle entries
Official summary
Service Bulletin for Remote-Fill DEF Tank Fill Port Torque Value and Required Lubricant. Some New Cascadia vehicles with chassis fairings have remote-fill Diesel Exhaust Fluid (DEF) tanks which have new instructions to replace the remote fill hose and fitting. Proper torque value is critical, as the remote-fill fittings are plastic and can easily crack if overtightened. The gasket on the fill fitting is sensitive to improper installation, and can get pinched, resulting in a DEF leak.
Vehicles covered
What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.