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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

Bulletins, newest first
FAB1462021-05-18. Service bulletin. VISIBILITY; EXTERIOR LIGHTING. Freightliner Action Bulletin FAB146 Cascadia LED headlights
FAB1452021-05-18. Service bulletin. STRUCTURE. Freightliner Action Bulletin FAB145 New Cascadia Roof Fairing
FTLCAE182-20172021-05-17. Service bulletin. POWER TRAIN; EQUIPMENT. New DT12 Transmission for Original Cascadia
FTLCAE173-20172021-05-17. Service bulletin. EQUIPMENT; POWER TRAIN. Air-to-Oil Coolers for DT12 in New Cascadia
FTLCAE172-20172021-05-17. Service bulletin. POWER TRAIN:MANUAL TRANSMISSION; EQUIPMENT. New Accuride Aluminum Wheels
FTLCAE167-20162021-05-17. Service bulletin. VISIBILITY; EQUIPMENT:APPLIANCE:AIR CONDITIONER; ELECTRICAL SYSTEM:12V/24V/48V BATTERY. Important Update for Parked HVAC System Options
TK-APU2021-05-10. Service bulletin. ELECTRICAL SYSTEM. Evolution APU No Regen.
TechTalk566191K2021-05-07. Service bulletin. ENGINE AND ENGINE COOLING. Tech Talk discussion on SPN 61683 FMI 16 DATA VALID BUT ABOVE NORMAL OPERATING RANGE - MODERATELY SEVERE LEVEL.
TechTalk200692021-05-05. Service bulletin. ELECTRICAL SYSTEM; SUSPENSION. Tech Talk discussion on 2021 NEW CASCADIA SUSPENSION DUMP IS NOT RAISING THE SUSPENSION.
SS3076-FTL20212021-05-01. Service bulletin. VISIBILITY. Service Solution for P4 Main Mirror Arm Covers Loose - Falling Off. Lower arm cover designs have clips that hold the cover on but over time the clips can fail and allow the covers to become loose or fall off.
SS3075-FTL20212021-05-01. Service bulletin. POWER TRAIN. Service Solution for FTL DT12 Trans Control Harness Chaffing - PT Can faults. Transmission will not shift into Gear while driving or will not start and trigger multiple PT CAN Fault Codes.
CALFTL40-0012021-05-01. Service bulletin. TIRES. Customer Advisory Letter for Tire Valve Stem Inspection.
D21M12021-05-01. Service bulletin. POWER TRAIN. Detroit Field Service Campaign for DT12 Transmission Drive Shaft Cover Plug Reseal. Daimler Trucks North America LLC, on behalf of its DETROIT Powertrain Division, is initiating Field Service Campaign D21M1 on certain DT12 transmissions in order to reseal the bypass plugs of the drive shaft cover located in front housing.
SF6182021-04-28. Service bulletin. ELECTRICAL SYSTEM. Field Service Campaign for Cascadia Cummins Acumen Edge Wiring. Certain vehicles equipped with a Cummins Acumen Edge module are not communicating and, therefore, are unable to benefit from over-the-air software updates and may not be able to connect to the Cummins digital apps.
SB54-3222021-04-28. Service bulletin. VISIBILITY. Updated Freightliner Service Bulletin for Adjusting Automatic Temperature Control Range with Optimized Idle. This bulletin replaces the version dated 12/06/2019. Tables 3 and 4 have been updated. Steps to change and match HVAC desired settings have been updated.
CALFTL54-0162021-04-24. Service bulletin. ELECTRICAL SYSTEM. Customer Advisory Letter for Battery Cable Access (BCA) 29A Cable Inspection.
WI21-0092021-04-24. Service bulletin. ENGINE AND ENGINE COOLING. Warranty Information letter announcing that DTNA is increasing the Standard Diagnostic Times (SDTs) shown. The updated after treatment system (ATS) diesel exhaust fluid (DEF) pump times will be applied to repair orders opened on or after April 12, 2021.
WI21-0082021-04-23. Service bulletin. EQUIPMENT. Warranty Information Letter announcing DTNA is adjusting the Standard Repair Times (SRTs) shown. The updated times will be applied to repair orders opened on or after April 5, 2021.
DT12 Trans Chafe2021-04-08. Service bulletin. EQUIPMENT; EQUIPMENT ADAPTIVE/MOBILITY; POWER TRAIN. DTNA received a field notification on multiple units regarding diagnostic fault codes that were found to be causing issues to the After Treatment Control Module (ACM). These fault codes indicated that the ACM communication message was not received by the Motor Control Module (MCM) which in certain cases, led to a 25% engine de-rate situation. Further diagnosis revealed that the DT12 wiring harness was chafing and contacting the transmission TCU case. To reduce potential chafing areas, the proposed short-term containment was to route the wiring harness using additional tie straps. This communication applies to Freightliner and Western Star vehicles built with DT12 transmissions.
TechTalk75412021-04-06. Service bulletin. ELECTRICAL SYSTEM; SEATS. Tech Talk continuing discussion on 523013/31 seat occupation not ok.
TechTalk12296K2021-04-05. Service bulletin. ELECTRICAL SYSTEM; LATCHES/LOCKS/LINKAGES. Tech Talk discussion on Door Control Module Driver (DCMD) failing.
SF6202021-04-01. Service bulletin. EQUIPMENT. Field Service Campaign for Freightliner Cascadia RHD Key Fob - Export Only. The Regulatory Compliance Marking (RCM) was not implemented on the Key Fobs shipped to the Australian/New Zealand Market, as required by AS/NZS 4417.1 and 4417.2. The marking indicates component compliance with the requirements imposed or covered by these regulations. Key Fob replacements for the right hand drive (RHD) Cascadia, properly marked for sale and distribution in Australia and New Zealand will be provided and programmed.
CALFTL42-0032021-03-31. Service bulletin. SUSPENSION; SERVICE BRAKES. Customer Advisory Letter for Inspection and Correction of the Clearance between the Drive Axle Disc Brake Chamber and the Airliner Leaf Spring.
SF6192021-03-31. Service bulletin. ENGINE AND ENGINE COOLING. Field Service Campaign for Cascadia Cummins Natural Gas Engine Exhaust Shield. On certain vehicles, there may be early heat degradation at the front right cab mount due to excessive heat exposure. An exhaust shield will be installed on all vehicles involved.
D21M32021-03-31. Service bulletin. POWER TRAIN. Detroit Field Service Campaign for DT12 Gear Grind During Downshift Software Update.

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