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Service bulletins for the 2025 Mack MD

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.

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

By type

By component

By trouble code

Bulletins, newest first
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.
TSB M-432-002A 0320262026-04-02. Service bulletin. POWER TRAIN. TSB - Cable, Gear Selector, Replacement
CBR 2712-7 0320262026-04-02. Service bulletin. ELECTRICAL SYSTEM; UNKNOWN OR OTHER. CBR - No Start Condition After Over the Air Programing.
CBR 2517-1 1020252025-11-03. Service bulletin. VISIBILITY/WIPER. CBR - Wiper Linkage Inspection.
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.
S4325 0720252025-08-04. Service campaign. ENGINE. CBR - Mack Trucks has identified that certain 2025 model year Mack Medium Duty (MMD) vehicles may have been assembled with insufficient torque on the fan hub retaining hardware.
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.
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-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
S4325 2024122025-01-02. Service campaign. ENGINE. Mack Trucks has identified that certain 2025 model year Mack Medium Duty (MMD) vehicles may have been assembled with insufficient torque on the fan hub retaining hardware. To address this issue and maintain Mack's high-quality standards, please follow the instructions below to properly retorque the fan hub retaining hardware.
CBR-2016 2024122025-01-02. Service bulletin. SUSPENSION. Frame lean can be caused by several seemingly isolated possibilities. The two most common are suspension and frame assembly issues.
CBR-997 2024112024-12-02. Service bulletin. ENGINE. Vehicles may present with oil leak coming from the clutch/flywheel housing and observation of burned clutch smell or clutch slipping. These symptoms can be mistaken as a crankshaft rear main seal leak, when the actual cause is the crankshaft adaptor O-ring.
CBR-407 2024092024-10-03. Service bulletin. SERVICE BRAKES. CBR: To correct the MID136 SID 66 FMI 7 fault code the latest Bendix VCP fi le will need to be downloaded.
CBR-2391 2024082024-09-04. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN. CBR: Diagnostic Trouble Code (DTC) U010187- Lost Communication With TECU
CBR-2350 2024072024-08-01. Service bulletin. ELECTRICAL SYSTEM. CBR: Telematics Gateway (TGW) Connect Ability Issues
CBR-2013 2024042024-05-01. Service bulletin. ENGINE AND ENGINE COOLING. CBR: Turbo Compound (TC) Hot Side Noise, Diagnostic Information.
CBR-1008 2024042024-05-01. Service bulletin. POWER TRAIN. CBR: Equipped With An Automated Manual Transmission Model D or F ( AMT-D, AMT-F, mDrive) Missing X1 Value In VDA And Default Settings Guidelines, ParameterP1AOB; Fault Code P1052-54, Error 40,Or Error 18 Encountered During Clutch Or Tran.
CBR-2139 2024032024-04-02. Service bulletin. ENGINE AND ENGINE COOLING. CBR: Vehicles built with an 11 liter engine may experience a complaint of excessive fuel in the oil. It is possible that the source of the fuel is the rear fuel galley plug in the cylinder head.

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