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Service bulletins for the 2020 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.

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

By type

By component

By trouble code

Bulletins, newest first
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-256-0012023-04-04. Service bulletin. ENGINE AND ENGINE COOLING. New TSB for air cleaner housing repair
KC-22592023-04-04. Service bulletin. ENGINE AND ENGINE COOLING. Oil In Coolant - Cross Contamination From Oil Cooler - 13L VGT Engines
S76272023-03-07. Service bulletin. ENGINE AND ENGINE COOLING. Mack MMD Alternator Pulley
S75672023-03-07. Service bulletin. ENGINE AND ENGINE COOLING. Electronic Pressure Releif Valve (EPRV) Delete & Fuel Rail Pressure Sensor
KC-22542023-03-07. Service bulletin. ELECTRICAL SYSTEM. Mack Chassis - No Gauge Cluster Backlight
KC-21652023-03-07. Service bulletin. ENGINE AND ENGINE COOLING. Mack DEF Pump Troubleshooting Guide - US10+OBD13 And Newer Emissions
KC-22482023-03-07. Service bulletin. POWER TRAIN; ENGINE AND ENGINE COOLING. Flywheel Housing Thread Repair
KC-22532023-03-07. Service bulletin. SUSPENSION. Barksdale Height Control Valve Troubleshooting Guide
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
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-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
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

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