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Service bulletins for the 2021 Mack Granite

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.

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

By type

By component

By trouble code

Bulletins, newest first
KC-3062023-03-07. Service bulletin. POWER TRAIN. Diagnostic Trouble Code ( DTC ) P10AE Logged In TECU With ACTIVE Or INACTIVE Status, Fault Code Cannot Be Cleared; Possibly Accompanied By P105817 And P105818 - US10+OBD13 And Newer Emissions (16-Pin Diagnostic Connector), Commonly Model Year 2014
KC-22532023-03-06. Service bulletin. SUSPENSION. Barksdale Height Control Valve Troubleshooting Guide
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
M-852-0012023-01-03. Service bulletin. SUSPENSION. 2007 document reformatted to be published as a TSB in Impact. Lateral cab movement bracket.
M-371-0042023-01-03. Service bulletin. EQUIPMENT:ELECTRICAL; VISIBILITY/WIPER. TBS- Jumper Harness,Wiper Motor,Replacement
P0244-00 (1)2022-12-06. Service bulletin. ENGINE AND ENGINE COOLING. Document revised to state that a software update has been released for P0244-00 on TurboCompound US20 - US21 Emission engines.
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.
KC-22162022-10-04. Service bulletin. ELECTRICAL SYSTEM. Mack Chassis - Incorrect Fog Lamp Electric Terminal Pinning - AN, GR, PI Models
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
M-652-0012022-09-01. Service bulletin. SUSPENSION. 2009 Document reformatted to be published as a TSB in Impact. Axle Alignment Specifications
KC-7332022-07-05. Service bulletin. ENGINE AND ENGINE COOLING. Back Office Mack Chassis - Secondary Gauge Set Up - Model Year 2018 and Newer.
KC-21072022-07-05. Service bulletin. ENGINE AND ENGINE COOLING. DEF Level (UQLS) Sensor Troubleshooting Guide - US17+OBD16 Emissions and Newer.
KC-21122022-07-05. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN; ENGINE AND ENGINE COOLING. Programming Failure - Chassis With Cummins Engine And An Allison Transmission
KC-21162022-07-05. Service bulletin. ENGINE AND ENGINE COOLING. NOx Sensor Troubleshooting Guide - US10+OBD13 And Newer Emissions.
KC-21432022-07-05. Service bulletin. VEHICLE SPEED CONTROL. (Back Office) - Cruise Control Inoperative After Updating Software VECU5 Without ESP Package (UESP).
KC-21572022-07-05. Service bulletin. ENGINE AND ENGINE COOLING; FUEL SYSTEM, GASOLINE. Aftertreatment Hydrocarbon Injector (AHI) Troubleshooting Guide - US10+OBD13 And Newer Emissions.
KC-21582022-07-05. Service bulletin. ENGINE AND ENGINE COOLING. Selective Catalytic Reduction (SCR) Muffler Troubleshooting Guide - US10+OBD13 And Newer Emissions.
KC-21652022-07-05. Service bulletin. ENGINE AND ENGINE COOLING. DEF Pump Troubleshooting Guide - US10+OBD13 And Newer Emissions.
KC-3992022-07-05. Service bulletin. ELECTRICAL SYSTEM. Vehicle Overspeed Warning Comes Active At A Lower Speed Than Expected; Vehicle Overspeed Warning In Driver Information Display (DID) - Model Year 2018 And Newer With New Style Instrument Cluster.
KC-4052022-07-05. Service bulletin. POWER TRAIN. Warranty Automated Manual Transmission ( AMT, I-Shift, mDrive ) Control Housing Assembly; Guidelines For Filing A Claim For Chassis Return Visit With Transmission Issues After A Repair Requiring Control Housing Removal And Reinstallation - US07 And N.

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