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Service bulletins for the 2021 Freightliner Cascadia

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

509 on file from NHTSA, as of 2026-10-19.

By type

By component

Only bulletins with component: Glass, wipers and mirrors are shown. Show all

Bulletins, newest first
Techtalk79772020-12-31. Service bulletin. VISIBILITY. Tech Talk discussion on rookie mirror falling out.
Techtalk77762020-12-31. Service bulletin. VISIBILITY; ENGINE AND ENGINE COOLING. Tech Talk continued discussion on 2021 Cascadia opt idle issues.
Techtalk70652020-12-31. Service bulletin. VISIBILITY. Tech Talk continued discussion on New Cascadia wipers unresponsive. Wipers don't work in the first two positions. Determined to be the LDW camera wire was caught underneath the top right portion of the windshield mounting plate, thus causing the rain/light sensor to not seat all the way against the windshield.
SB54-3382020-12-30. Service bulletin. VISIBILITY; EQUIPMENT. Freightliner Service Bulletin for Front HVAC Evaporator Freezing and Espar Heater Cool Down Algorithm. New Cascadia vehicles with sleeper cabs may become extremely cold when in A/C mode, which can lead to reduced airflow as a result of internal ice buildup at the evaporator. Durability of the Espar D5 heater system when paired with the battery parked HVAC system (BPHS) can be improved by applying "cool down" software to the parked control unit (PCU).
TechTalk48552020-09-30. Service bulletin. ELECTRICAL SYSTEM; VISIBILITY; INTERIOR LIGHTING. Tech Talk discussion for P4 Next Gen Cascadia dome lights stay on while driving.
SB54-3312020-09-16. Service bulletin. VISIBILITY; EXTERIOR LIGHTING; ELECTRICAL SYSTEM. Updated Freightliner Service Bulletin for Updated ULB Control Unit for LED Headlamps. This bulletin replaces the version dated July 30, 2020. Information about a reman part has been added. New Cascadia vehicles with light emitting diode (LED) headlamps built from January 1, 2017 through February 17, 2020 may experience intermittent disabled headlamps due to an issue with the universal light ballast (ULB). The LED headlamps can turn off if the supply voltage drops below approximately 9V. This low voltage commonly and momentarily occurs when cranking the engine on a vehicle with batteries that are not fully charged. The momentary low voltage may cause the electronic ULB control unit to malfunction. The ULB may not resume normal function until the power supply to the headlamp is disconnected.
SB54-3312020-07-31. Service bulletin. ELECTRICAL SYSTEM; EXTERIOR LIGHTING; VISIBILITY. Freightliner Service Bulletin for Updated ULB Control Unit for LED Headlamps. New Cascadia vehicles with light emitting diode (LED) headlamps built from January 1, 2017 through February 17, 2020 may experience intermittent disabled headlamps due to an issue with the universal light ballast (ULB). The LED headlamps can turn off if the supply voltage drops below approximately 9V. This low voltage commonly and momentarily occurs when cranking the engine on a vehicle with batteries that are not fully charged. The momentary low voltage may cause the electronic ULB control unit to malfunction. The ULB may not resume normal function until the power supply to the headlamp is disconnected.
SS10347582020-07-28. Service bulletin. EQUIPMENT:ELECTRICAL; VISIBILITY. Service Solution for New Cascadia Window Regulator Motor Stop Working. The window regulators motors are not designed to be run continuously. The window regulator motors have a thermal cutoff. If they are run long enough, there will eventually be an open circuit and get a fault code.
SB31-0442020-07-28. Service bulletin. VISIBILITY. Service Bulletin for Reflective Tape Installation. If a truck tractor is ordered without mudflaps and/or mudflap support brackets, the rear reflective tape applied to the mudflaps or mudflap brackets during production is delivered loose with the vehicle. FMVSS/CMVSS 108 S5.7.1.4.3 requires reflective tape on all truck tractors domiciled in the United States and Canada.
SB60-1682020-04-18. Service bulletin. VISIBILITY; STRUCTURE. Service Bulletin for Installing Rain Gutters for Upper Door Seal Leaks. New Cascadia day cab vehicles with roof fairings may experience minor water leaks through the upper door seals. This issue can be minimized by regularly wiping down the door seals to keep them free of road grime. A rain gutter seal can also be installed above each door using a Cascadia tertiary seal (part number 18-63286-002).
SB60-1692020-04-18. Service bulletin. VISIBILITY. Service Bulletin for Replacing Windshield Gasket. Different types of cab leaks can result in water dripping from the top of the windshield, onto the dash. Replacing a windshield gasket unnecessarily may create new leak issues. Do not replace a windshield gasket unless it has been confirmed to leak, using the cab pressure test.
SB54-3242020-02-15. Service bulletin. EXTERIOR LIGHTING; VISIBILITY. Service Bulletin for certain New Cascadia equipped with Detroit Assurance 5.0, may have been ordered incorrectly without automatic headlamps and rain sensing wipers. If equipped with Detroit Assurance 5.0, daytime running lights (DRL), no exterior sun visor, and no cruise control options that disengage with the headlights or wipers, the automatic headlamps and wipers can be retrofitted.

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.