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Service bulletin FSB593013

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.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id10083480
Published by NHTSA2016-10-25
Manufacturer's numberFSB593013
Manufacturer's date2014-10-13
NHTSA componentEQUIPMENT:MECHANICAL; EQUIPMENT:ELECTRICAL

NHTSA's summary

"GRADE GRIPPER SOLENOID, REPLACEMENT. ON SOME MACK CHU, CXU, GU, AND TD TRUCK MODELS BUILT BETWEEN 04/31/2008 AND 05/12/2014, THE SOLENOID VALVE FOR THE GRADE GRIPPER FEATURE IS PRONE TO INTERNAL CONTAMINATION IN HARSH ENVIRONMENTS. THE INTERNAL CONTAMINATION OF THE SOLENOID VALVE IS CAUSED BY THE BUILDUP OF GRIME, SALT, ROAD DEBRIS AND OTHER SOLID CONTAMINANTS. IN SOME CASES, THE BUILD-UP OF SOLID CONTAMINANTS CAUSED THE SOLENOID VALVE TO MALFUNCTION. THE MALFUNCTION CAUSES THE TRAILER BRAKE CIRCUIT TO MAINTAIN TRAILER BRAKE PRESSURE AFTER A GRADE GRIPPER EVENT. REPLACEMENT OF THE EXISTING SOLENOID VALVE, ELBOW, AND THE ADDITION OF A NEW VENT WILL ENSURE PROPER FUNCTIONALITY OF THE GRADE GRIPPER FEATURE. "

The document

No address for NHTSA's copy can be built for this communication. Ask the dealer for it by the manufacturer's number.

Components

Equipment and accessories

Vehicles listed
MACK CHU2009 to 2015
MACK CXU2009 to 2015
MACK GU2009 to 2015
MACK TD2009 to 2015

Listing a model year does not mean every vehicle of it is concerned: the document says which.