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Service bulletins for the 2021 Mack LR

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.

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

By type

By component

By trouble code

Bulletins, newest first
KC-4152022-02-04. Service bulletin. ENGINE AND ENGINE COOLING. Diagnostic Trouble Code ( DTC ) P26E8 Intermittently Lighting The Malfunction Indicator Lamp ( MIL ); Possible Derate Warning - US10+OBD13 And Newer Emissions, Model Year 2014 And Newer
KC-4062022-02-04. Service bulletin. FUEL SYSTEM, DIESEL. Dye Test Procedure; Fuel System Leak Check - Common Rail Fuel System - US17+OBD16 And Newer Emissions, Common Model Year 2018 And Newer
KC-4012022-02-04. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL. Diagnostic Trouble Codes (DTC) P24F600 Or P24F700 - US14+OBD15 Emissions And Newer, Model Year 2016 And Newer
KC-4062022-02-04. Service bulletin. EQUIPMENT; FUEL SYSTEM, DIESEL. Dye Test Procedure; Fuel System Leak Check - Common Rail Fuel System - US17+OBD16 And Newer Emissions, Common Model Year 2018 And Newer
KC-4022022-02-04. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL; ELECTRICAL SYSTEM. Volvo Chassis - Diagnostic Trouble Code (DTC) SA 0 FMI 0 or SPN 0 FMI 0 Present On Fault Code Readout - US10 And Newer Emissions, Model Year 2011 And Newer
KC-3912022-02-04. Service bulletin. EQUIPMENT:ELECTRICAL:RADIO/TAPE DECK/CD ETC.. Noise On The AM Radio Band; Thumping, Ticking, Fluttering Sound On AM Radio Band - Model Year 2018 And Newer
KC-3832022-02-04. Service bulletin. LANE DEPARTURE. Mack Chassis - Equipped With Bendix Fusion, With Or Without Lane Departure Warning ( LDWS ) - Diagnostic Trouble Code ( DTC ) SPN 70 FMI 9, Bendix Code 64 With Possible "Lane Departure Warning Malfunction" Message - US17 And Newer
KC-3542022-02-04. Service bulletin. ELECTRICAL SYSTEM; ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL. Volvo Chassis - Certain Volvo Trucks Built After January 11, 2016 May Experience an Issue with the Instrument Cluster Display
KC-20432022-01-08. Service bulletin. ENGINE AND ENGINE COOLING; ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM):SOFTWARE; ELECTRICAL SYSTEM:SOFTWARE. Engine Control Module (EMS) Software (MSW) Information - Improvement List, November 2021 - US21+OBD2020 Emissions
GDC21-0112022-01-07. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:OIL/LUBRICATION:PRESSURE/TEMPERATURE SENSOR; ENGINE AND ENGINE COOLING. Exhaust Gas Temperature Sensor Circuit Range/Performance
KC-2862022-01-06. Service bulletin. SERVICE BRAKES, AIR; UNKNOWN OR OTHER. Mack Chassis - FSB 563-008 Plugs, Pressure Protection Manifold - New Brass Plugs For Noregon Pressure Protection Manifold (PPM)
KC-2752022-01-06. Service bulletin. ENGINE AND ENGINE COOLING. (Back Office Only) Vehicles Equipped With A Turbo Compound Engine - Report Of Frequent Air Compressor Cycling. Secondary Air System Air Pressure Decreases Slowly When Engine Is At Low Idle - US17+OBD16 And Newer Emissions, Model Year 2018 And Newer
KC-2382022-01-06. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL. Mack Chassis - Where To Find The Body Builder Portal - Body Builder Manual ( BBM ) Information - US04 And Newer Emissions, Model Year 2008 And Newer
KC-1932021-12-07. Service bulletin. ENGINE AND ENGINE COOLING. Mack Chassis - Particulate Matter (PM) Sensor Diagnostic Trouble Codes (DTC) Illuminating The Malfunction Indicator Lamp (MIL); Tech Tip TT-014-2016 - US14+OBD16, US17+OBD16 And Newer Emissions, Common Model Year 2017 And Newer - To Be Used For EVERY
KC-1672021-12-07. Service bulletin. ENGINE AND ENGINE COOLING. Premium Tech Tool (PTT) Error Code 43: Service Regeneration Fails To Start; Service Regen Does Not Complete With Error 43 Displayed - US10+OBD13 And Newer Emissions, Common Model Year 2014 And Newer
KC-1632021-12-07. Service bulletin. FUEL SYSTEM, DIESEL. Diesel Fuel Information - Acceptable Biodiesel, Fuel Blend For Summer And Winter - US07 And Newer Emissions, Model Year 2008 And Newer
KC-1592021-12-07. Service bulletin. ENGINE AND ENGINE COOLING. Trucks Equipped With A Cummins Engine - Engine Preheat Icon Does Not Illuminate In The Instrument Cluster (IC) During Engine Pre-heat (Intake Air Heater) Operation - Vehicles With 2018 Instrument Cluster Update, Model Year 2018 And Newer
KC-1452021-12-07. Service bulletin. POWER TRAIN. Automated Manual Transmission (AMT) (Spigot Bearing) Input Shaft Repair Kit And Shim Kit, Part Number Information, Reference Guide - US07 And Newer Emissions, Model Year 2008 And Newer
KC-1192021-12-07. Service bulletin. POWER TRAIN. Mack Chassis - Equipped With An Automated Manual Transmission (mDrive, AMT) AMT-C, AMT-D Or AMT-F - Transmission Oil Specifications - Model Years 2010 To 2020
KC-1362021-11-05. Service bulletin. ENGINE AND ENGINE COOLING. Aftertreatment Control Module (ACM) Offline/Not Visible/Missing From Control Unit Information in Premium Tech Tool (PTT) - US10+OBD13 And Newer Emissions
KC-1302021-11-05. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM); FUEL SYSTEM, OTHER. Air In The Fuel System Tests, Common Rail Fuel System - US17+OBD16 and Newer Emissions
KC-1242021-11-05. Service bulletin. POWER TRAIN. Automated Manual Transmission Gearbox Will Not Shift To High Range After Gearbox Repair; MID 130 PSID 24 FMI 1, P1072-92 Unintentional Disengagement Of High Range - US07 And Newer Emissions, Model Year 2008 And Newer
KC-1152021-11-05. Service bulletin. POWER TRAIN; POWER TRAIN:AUTOMATIC TRANSMISSION:INTERNAL:GEARS. Automated Manual Transmission ( AMT ) ( I-Shift, mDRIVE ) Equipped Chassis, OBD13 And Newer - Light Turbo Surge ( Chuff ) During Skip Shifting
S76102021-11-05. Service bulletin. SERVICE BRAKES, AIR; SERVICE BRAKES, AIR:SLACK ADJUSTERS; SUSPENSION:SUBFRAME/MOUNTING BRACKET. Bump Stop Interference with Brake Slack
SNM21-0062021-11-04. Service bulletin. COMMUNICATION:MANUFACTURER TELEMATICS; UNKNOWN OR OTHER; ELECTRICAL SYSTEM:SOFTWARE. Remote Software Downloads

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