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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
SLM23-0052023-06-06. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. Service Literature Published and Released in May, 2023
KC-20502023-06-05. Service bulletin. ENGINE AND ENGINE COOLING. CBR: Diagnostic Trouble Code (DTC) P225C00 : NOx1 Sensor Stuck High - US17+OBD2019 And Newer Emissions
KC-331-Ver62023-06-05. Service bulletin. FUEL SYSTEM, DIESEL. CBR: Model Year 2017 to Current - Fuel Filter Change ( Primary And Secondary ) For The EM - USA17 Emission Engines
KC-503-Ver32023-06-05. Service bulletin. POWER TRAIN. CBR: Automated Manual Transmission ( AMT ) -Transmission Electronic Control Unit ( TECU ) MID130 PSID 29 FMI 7 /P10AE81 Fault Codes Being Generated
KC-2229-Ver22023-06-05. Service bulletin. POWER TRAIN. CBR: Automated Manual Transmission (AMT) Transmission Kickdown Mode
KC-474-Ver52023-06-05. Service bulletin. POWER TRAIN. CBR: Diagnostic Trouble Code (DTC) P215A-64, Fault Code SPN 84 FMI 19
KC-2012-Ver32023-06-05. Service bulletin. SERVICE BRAKES. CBR: SNM 20-005 - HD Disc Brake Rotor Upgrade
KC-2263-Ver52023-06-05. Service bulletin. ENGINE AND ENGINE COOLING. CBR: Timing Gear Plate Repair. This solution provides supplementary information to be used when installing a Timing Gear Plate with Integrated Seal.
M-773-005a2023-05-03. Service bulletin. WHEELS. TSB: Hub Cap, Leaking
KC-22642023-05-03. Service bulletin. ELECTRICAL SYSTEM. CBR: Mack Chassis - Allison Reduced Engine Load At A Stop (RELS) Diagnostic Trouble Code P071a Or P07ce - GR,TE,LR Models - Non-Split/Drop Box PTO
KC-22692023-05-02. Service bulletin. ENGINE AND ENGINE COOLING. CBR: 11L Engines, Non-Common Rail - Air Compressor Coolant Pipe, Parts Substitution - US14+OBD13 To US14+OBD16
M-773-0052023-04-04. Service bulletin. WHEELS. New TSB- Hub cap leaking
KC-21282023-04-04. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL; ELECTRICAL SYSTEM. Engine Control Module (EMS) Software Information - Improvement List (Change Log), March 2023 – US21+OBD2021 Emissions ONLY
S76272023-03-07. Service bulletin. ENGINE AND ENGINE COOLING. Mack MMD Alternator Pulley
KC-22442023-03-07. Service bulletin. STRUCTURE:FRAME AND MEMBERS; SUSPENSION. Mack Model TE,LR - Frame Over Height
KC-21652023-03-07. Service bulletin. ENGINE AND ENGINE COOLING. Mack DEF Pump Troubleshooting Guide - US10+OBD13 And Newer Emissions
KC-22012023-01-07. Service bulletin. ELECTRICAL SYSTEM. Engine Control Module (EMS) Software (MSW) Information – October 2022; Improvement List (Change Log) - US21+OBD22 (13L VGT, TC) And US17+OBD22 (11L) Emissions
M-212-0012023-01-04. Service bulletin. ENGINE AND ENGINE COOLING. Timing Gear Plate Inspection
KC-21402022-12-05. Service bulletin. ELECTRICAL SYSTEM; PARKING BRAKE. Mack Chassis - P05E662 Park brake Sensor/Switch Circuit Range/Performance, Signal Compare failure - Diagnostic Instructions - US21+OBD21 Emissions
KC-3282022-12-05. Service bulletin. ELECTRICAL SYSTEM. Diagnostic Trouble Codes (DTC) P208064, P208464, P242B64 and P246F64 Lighting The Malfunction Indicator Lamp (MIL) - US17+OBD19 And Newer Emissions, Model Years 2020 and Newer
KC-21652022-11-03. Service bulletin. ENGINE AND ENGINE COOLING; ENGINE AND ENGINE COOLING:EXHAUST SYSTEM. Mack DEF Pump Troubleshooting Guide - US10+OBD13 And Newer Emissions
M-265-0022022-10-06. Service bulletin. ENGINE AND ENGINE COOLING. TSB-Charge Air Cooler t-clamp install.
CBR-21312022-09-08. Service bulletin. ENGINE AND ENGINE COOLING. USE FOR NEW VEHICLES (US21+OBD22 Emissions) - Intermittent Diagnostic Trouble Codes U02A3, U029D, U029E
KC-21392022-09-07. Service bulletin. ENGINE AND ENGINE COOLING; FUEL SYSTEM, DIESEL. fuel in the oil inspection
KC-7332022-07-05. Service bulletin. ENGINE AND ENGINE COOLING. Back Office Mack Chassis - Secondary Gauge Set Up - Model Year 2018 and Newer.

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