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Service bulletins for the 2021 Mack Anthem

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.

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

By type

By component

By trouble code

Bulletins, newest first
CBR 159 2026082026-09-01. Service bulletin. ELECTRICAL SYSTEM. Mack 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 2018Instrument Cluster Update, Model Year2018 And Newer
CBR 2575-1 2026042026-05-05. Service bulletin. STRUCTURE:BODY; UNKNOWN OR OTHER. CBR - Mack Chassis - Dash Panel Cracking at Mounting to BIW.
CBR 2573-1 2026042026-05-05. Service bulletin. POWER TRAIN. CBR - Mack Chassis - Through Shaft Bearing Retainer Breakage On Mack Carriers.
CBR 2362-3 2026042026-05-04. Service bulletin. POWER TRAIN. CBR - Mack Carrier Nut Adhesive Change.
M0039 0320262026-04-02. Emissions. ENGINE. Emissions - EC0039 MST21 Failure to Detect P20EE - AN, CHU.
CBR 2246-5 0320262026-04-02. Service bulletin. SUSPENSION. CBR - Z Spring Bracket Wear.
CBR 2712-7 0320262026-04-02. Service bulletin. ELECTRICAL SYSTEM; UNKNOWN OR OTHER. CBR - No Start Condition After Over the Air Programing.
CBR 2432-2 2026012026-02-03. Service bulletin. STRUCTURE:BODY; VISIBILITY/WIPER. CBR - Mack Chassis - AN And GR Models - Door Glass Shattering.
CBR 2107-22 2026012026-02-02. Service bulletin. ENGINE. CBR - Mack DEF Level (UQLS) Sensor Troubleshooting Guide - US17+OBD16 Emissions to US22+OBD2023 (DOES NOT APPLY TO AN(4) and PR(4)).
CBR 199 2025122026-01-05. Service bulletin. ENGINE. Vehicles affected by this issue will show coolant runoff on the front rights side of the engine.
CBR 2171-11 2025112025-12-03. Service bulletin. ENGINE; ELECTRICAL SYSTEM. CBR - Mack Temperature Sensor Troubleshooting Guide
CBR 199-6 2025112025-12-03. Service bulletin. ENGINE. CBR - 13 Liter Engines ONLY - Engine Coolant Pump Housing Leak; Coolant Found Around The Oil Cooler Duct Cover Or In Between The Coolant Pump Housing And Oil Cooler Housing.
CBR 2172-5 0820252025-09-02. Service bulletin. ELECTRICAL SYSTEM. CBR - When an OTA (Over-The-Air) job starts to program the VECU blocks the starter relay out, if the job ends in a Critical failure, the vehicle will remain in Safe State.
CBR 407 0720252025-08-04. Service bulletin. SERVICE BRAKES; ELECTRICAL SYSTEM. CBR - To correct the MID136 SID 66 FMI 7 fault code the latest Bendix VCP file will need to downloaded.
CBR 2488 0720252025-08-04. Service bulletin. ELECTRICAL SYSTEM. CBR - A significant GPS reporting issue is affecting fleet operations, with trucks maintaining back-office communication but failing to transmit GPS location data.
S4548 2025062025-07-01. Service campaign. STRUCTURE:BODY; UNKNOWN OR OTHER. Mack Trucks has determined that certain model year 2020 to 2022 Anthem trucks could experience excessive wear on the hood latch pins causing the hood to rattle during normal vehicle operation.
CBR 2464-1 2025052025-06-02. Service bulletin. POWER TRAIN. Mack Chassis - Rear Axle Overheat
CBR 2107-21 2025052025-06-02. Service bulletin. FUEL/PROPULSION SYSTEM; ENGINE. Mack DEF Level (UQLS) Sensor Troubleshooting Guide - US17+OBD16 Emissions and Newer
CBR 901-5 2025052025-06-02. Service bulletin. ELECTRICAL SYSTEM. Remote Control Central Door Lock, Programming; Key Fob Cannot Be Programmed Or Does Not Work After Programming - Model Year 2018 And Newer
CBR 445- 11 2025052025-06-02. Service bulletin. FUEL/PROPULSION SYSTEM. Vehicles Equipped With a Common Rail Fuel System - Aftermarket Secondary Fuel Filters, Important Information On Approved Filters - US17+OBD16 toUS21+OBD23
CBR 170-8 2025052025-06-02. Service bulletin. ENGINE. Inactive Code P25AE00 Being Generated After A Hard Pull And A Momentary Drop In Engine Oil Pressure (Low Oil Pressure) (Possible Related Codes - SPN4811 , SPN 100 , PID 100)
CBR-2452 2025032025-04-02. Service bulletin. ELECTRICAL SYSTEM. If the vehicle door is open and the truck is in neutral, a popup message may appear on the Driver Information Display (DID) instructing the operator to shift into neutral. If this message appears while the vehicle is already in neutral, the Instrument Cluster (IC)requires a software update.
CBR-2449 2025032025-04-02. Service bulletin. ENGINE. Cummins Exhaust Aftertreatment System (EATS) catalysts may experience cracking, which may be attributed to excessive vertical vibration in the exhaust stack. To mitigate this issue, a modification to the exhaust stack length is required.
CBR-561 2025032025-04-02. Service bulletin. ENGINE. If oil dilution is suspected refer to the applicable CBR solution below: ∙ CBR-659􀁡Mack Chassis - Oil Diluted With Fuel; Fuel In Oil, Diagnostic Information - All Emissions, All Model Years
CBR-2024 2025022025-03-04. Service bulletin. SERVICE BRAKES. CBR - There have been a few trucks that have not passed the chuff test due to hose configuration and the software monitors not allowing for system or driver variables. This ABS software and hardware change will address both.

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