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Service bulletin PI1391

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 id10139418
Published by NHTSA2018-06-04
Manufacturer's numberPI1391
Manufacturer's date2015-01-15
NHTSA componentENGINE AND ENGINE COOLING

NHTSA's summary

This preliminary informational bulletin provides a diagnostic tip for coolant leak at oil cooler inlet pipe o-ring after service engine replacement.

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Engine

Vehicles listed
CHEVROLET C SERIES2003 to 2009
CHEVROLET CONVENTIONAL2003
CHEVROLET EXPRESS2006, 2007, 2008, 2009, 2010
CHEVROLET SILVERADO 15002001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 (the catalog's model; the bulletin names a series or trim of it)
CHEVROLET SILVERADO 1500 HD2002, 2003, 2004, 2005 (the catalog's model; the bulletin names a series or trim of it)
CHEVROLET SILVERADO 25002001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 (the catalog's model; the bulletin names a series or trim of it)
CHEVROLET SILVERADO 35002001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 (the catalog's model; the bulletin names a series or trim of it)
CHEVROLET T SERIES2003, 2004, 2005
CHEVROLET T SERIES2010
GMC C SERIES2004 to 2006
GMC G SERIES2003
GMC GM2001 to 2002
GMC SAVANA2006, 2007, 2008, 2009, 2010
GMC SIERRA 15002001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 (the catalog's model; the bulletin names a series or trim of it)
GMC SIERRA 25002001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 (the catalog's model; the bulletin names a series or trim of it)
GMC SIERRA 35002001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 (the catalog's model; the bulletin names a series or trim of it)
GMC SIERRA DENALI2007, 2008, 2009, 2010 (the catalog's model; the bulletin names a series or trim of it)
GMC TOPKICK2003 to 2010

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

Recalls for the same vehicles and component
20073632007-11-09. Engine
07V5210002007-11-07. ENGINE AND ENGINE COOLING
06V2890002006-08-03. ENGINE AND ENGINE COOLING

A recall listed here may apply to some of the same vehicles. Only the manufacturer can say whether it applies to one vehicle.

Other bulletins for the same vehicles and component
00-06-01-026R2025-12-03. Service bulletin. This service bulletin provides information on replacing the intake manifold when the engine is replaced after severe internal engine damage.
23-NA-1532025-10-25. Service bulletin. The service bulletin advises the tech of a normal transmission shift condition and the delay in throttle response when the throttle plate is opened rapidly and advises the customer that it is normal for the delay.
03-06-01-023I2025-01-17. Service bulletin. This service bulletin explains how to measure for oil consumption and possible reasons for loss of oil.
19-NA-2192024-12-17. Service bulletin. This diagnostic tip bulletin provides additional information on how to diagnose a possible valve, lifter or camshaft issue.
04-06-01-029K2024-12-04. Service bulletin. This informational bulletin explains Unscheduled Supplemental Services and the importance of GM Simplified Maintenance Schedules.
03-06-01-023H2024-11-14. Service bulletin. This service bulletin explains how to measure for oil consumption and possible reasons for loss of oil.
01-06-01-011Q2024-11-13. Service bulletin. This service bulletin provides guidelines and diagnostic/repair information to technicians regarding vehicle engine oil consumption.
20-NA-1382024-11-05. Service bulletin. This bulletin provides information on Policies Applicable to All U.S. Dealers for Engine and Transmission Assembly Replacement Under Warranty, Policy or Customer Enthusiasm and information on Submission of Warranty Transaction in Global Warranty Management.
04-06-04-051J2024-10-31. Service bulletin. This service bulletin provides information for maintenance cleaning of the fuel injectors and gasoline detergent additive.
04-06-04-051J2024-10-31. Service bulletin. This service bulletin provides information for maintenance cleaning of the fuel injectors and gasoline detergent additive.