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Service bulletins for the 2020 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.

177 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.
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 2171-11 2025112025-12-03. Service bulletin. ENGINE; ELECTRICAL SYSTEM. CBR - Mack Temperature Sensor Troubleshooting Guide
CBR 2515-1 1020252025-11-03. Service bulletin. STEERING. CBR - Hard Steering Due to Steering Column Miter Box Corrosion – Inspection and Replacement Procedure
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 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-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-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-2263 2024102024-11-04. Service bulletin. ENGINE. CBR - Mack Chassis - Timing Gear Plate Repair
CBR-731 2024092024-10-03. Service bulletin. POWER TRAIN. CBR: Automated Manual Transmission (AMT) Model D or F (mDrive and I-Shift, AMT-D, AMT-F) - Transmission Oil Leakage From Transmission Input Shaft Seal Or Output Shaft Seal - US10 And Newer Emissions, Common Model Years 2010 And Newer
CBR-570 2024092024-10-03. Service bulletin. ELECTRICAL SYSTEM; FUEL/PROPULSION SYSTEM. CBR: US17 GHG Common Rail Fuel System Component Electrical Faults - Model Year 2017 To 2024
CBR-471 2024092024-10-03. Service bulletin. ELECTRICAL SYSTEM. CBR: The procedure to eliminate the Mack Chassis "Air Restriction Light On" seen in the cluster is to confirm that the parameter YYT is set to "Enable" with Premium Tech Tool.
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-561 2024082024-09-04. Service bulletin. ENGINE. CBR: 11L, 13L, And 16L Engine Oil Analysis Specifications - US10 And Newer Emissions
CBR-523 2024082024-09-04. Service bulletin. ENGINE. CBR: Overhead Wear Overview - Model Year2018 To Current (Common Rail Fuel System ONLY)
CBR-2350 2024072024-08-01. Service bulletin. ELECTRICAL SYSTEM. CBR: Telematics Gateway (TGW) Connect Ability Issues
CBR-2383 2024062024-07-03. Service bulletin. UNKNOWN OR OTHER; ELECTRICAL SYSTEM; VEHICLE SPEED CONTROL. CBR - Accelerator Pedal: Inspection Instructions
CBR-2139 2024052024-06-04. Service bulletin. FUEL/PROPULSION SYSTEM; ENGINE. 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. A new and improved fuel galley plug has been developed to resolve this issue.

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