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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

Only bulletins with component: Engine are shown. Show all

Bulletins, newest first
S74482020-03-09. Service bulletin. ELECTRICAL SYSTEM:IGNITION; EQUIPMENT; ENGINE. IGNITION CYLINDER REPLACEMENT-CUMMINS ENGINE
K420650422020-02-24. Service bulletin. ENGINE AND ENGINE COOLING. Mack Chassis - 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 2018 Instrument Cluster Update, Model Year 2018 And Newer
K535805142020-01-13. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; EQUIPMENT; ENGINE. Brake Drum Inspection - Checking Runout, Wear, And Other Characteristics
K292957442020-01-13. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; ENGINE AND ENGINE COOLING:ENGINE:DIESEL; EQUIPMENT. Updated PM Sensor Removal Procedure - US17+OBD16 and Newer Emissions
K889928922020-01-13. Service bulletin. FUEL SYSTEM, GASOLINE; ENGINE; EQUIPMENT; EQUIPMENT ADAPTIVE/MOBILITY. Assembled Camshaft - Injector Lobe Rotation Inspection For Possible Spun Camshaft Lobe; Diagnostic Trouble Codes (DTC) P0257-00, P2A17-00, Or P2A1F-00, Possible Lack Of Power - US17+OBD16 and Newer Emissions
K582036032019-12-09. Service bulletin. ENGINE AND ENGINE COOLING. Diagnostic Trouble Code (DTC) P20EE - SCR NOx Catalyst Efficiency Below Threshold (Bank 1) - US17+OBD2019 Emissions, Model Year 2020 ONLY
K809300882019-12-09. Service bulletin. ENGINE AND ENGINE COOLING. Diagnostic Trouble Codes ( DTC ) P0016-76 - Crankshaft Position - Camshaft Position Correlation - Turbo Compound ( TC ) - Model Year 2018 and Newer
K300241432019-10-28. Service bulletin. ENGINE AND ENGINE COOLING. Mack Chassis - Oil Diluted With Fuel; Fuel In Oil, Diagnostic Information - All Emissions Prior To US17+OBD16 (Common Rail Fuel System), Model Year 2017 And Older
K059135802019-10-28. Service bulletin. ENGINE AND ENGINE COOLING. 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 - Model Years 2019 And 2020
K869000432019-07-15. Service bulletin. ENGINE AND ENGINE COOLING. Exhaust Gas Recirculation (EGR) System - Fault Codes SPN 412 FMI 0,2,5; Diagnostic Trouble Codes (DTC) P040A, P040B, P1121 - Temperature Sensor Inspection
K272307372019-07-01. Service bulletin. ENGINE AND ENGINE COOLING; ENGINE. Mack Chassis - Granite Models (GU, GR) - Revised Fan Ring Design; Engine Cooling Fan Ring Cracked At Welds - Model Years 2016 To 2020
K367637342019-05-20. Service bulletin. ELECTRICAL SYSTEM; ENGINE. 13L Engines - High Engine Oil Pressure, Frequently Accompanied By P0521-64 Oil Pressure Sensor - Plausibility Fault
K655277082019-05-20. Service bulletin. ENGINE. Diagnostic Trouble Codes (DTC) P20EE And P103C, Diagnostic Procedure; REPLACES GUIDED DIAGNOSTICS IN PREMIUM TECH TOOL ( PTT ) - US17+OBD16 And Newer Chassis ONLY
K735350382019-05-20. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:GASOLINE:BELTS AND ASSOCIATED PULLEYS. Mack Chassis - Equipped With A Cummins 9 Liter Engine - Serpentine Belt Excessively Worn Or Damaged; Fan Belt Shredding Or Fraying Repeatedly
K525354912019-05-20. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL:GAS RECIRCULATION VALVE (EGR VALVE). Diagnostic / Troubleshooting Procedures For EGR System Components; Diagnostic Trouble Codes (DTC) P0401-00, P0402-00, P04DD-00, P1121-00, P1121-98 Or SPN 2659 FMI 16, SPN 2659 FMI 18, SPN 412 FMI 0, SPN 412 FMI 15 - US10, US10+OBD13, US14+OBD*, US17+OBD* With A Variable Geometry Turbocharger (VGT)
FSB563-0082019-05-20. Service bulletin. ENGINE; ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:MANIFOLD/HEADER/MUFFLER/TAIL PIPE. Plugs, Pressure Protection Manifold
K912146782019-04-22. Service bulletin. EQUIPMENT; POWER TRAIN; ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL. Automated Manual Transmission (AMT) Faults - Diagnostic Trouble Codes (DTC) P1052-18 Or MID 130 PID 33 FMI 5 Intermittent Fault In Cold Weather - US07 And Newer Emissions, Model Year 2008 And Newer

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