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Service bulletins for the 2025 Mack Pioneer

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.

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

By type

By component

By trouble code

Only bulletins with component: Fuel system are shown. Show all

Bulletins, newest first
GDC25-007 0920252025-09-29. Service bulletin. FUEL/PROPULSION SYSTEM. Reductant Injection Valve Control Bank 1 Unit 1 - Circuit Open
GDC25-004 0920252025-09-29. Service bulletin. FUEL/PROPULSION SYSTEM. Reductant Pressure Sensor - Circuit Open
GDC25-003 0920252025-09-29. Service bulletin. FUEL/PROPULSION SYSTEM. Reductant Return: No Flow Detected
GDC25-002 0920252025-09-29. Service bulletin. FUEL/PROPULSION SYSTEM. Low Fuel Pressure
CBR 2431 0720252025-08-04. Service bulletin. FUEL/PROPULSION SYSTEM. CBR - This CBR solution addresses crank no start and engine dying issues in some VN (4) and PR (4) models caused by an incorrect fuel line configuration and/or fuel line fitting not seated correctly.
CBR 2425 0720252025-08-04. Service bulletin. FUEL/PROPULSION SYSTEM. CBR - This CBR solution outlines the analysis of temperature changes in sensors T1, T2, and T3 and provides a procedure for inspecting and addressing potential sensor issues related to AHI fuel injection.
CBR 2107-21 2025052025-06-02. Service bulletin. FUEL/PROPULSION SYSTEM; ENGINE. Mack DEF Level (UQLS) Sensor Troubleshooting Guide - US17+OBD16 Emissions and Newer
S4342-2025022025-03-03. Service bulletin. FUEL/PROPULSION SYSTEM; ENGINE. Mack Trucks has determined that a select group of trucks were built with an AHI Module fuel pressure sensor which does not meet our specifications.

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