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Service bulletin 311001

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 id628070
Published by NHTSA2002-03-05
Manufacturer's number311001
Manufacturer's date2001-10-31
NHTSA componentENGINE AND ENGINE COOLING:EXHAUST SYSTEM

NHTSA's summary

SOME VEHICLES MAY EXHIBIT AN EXHAUST NOISE, RATTLE NOISE AT 550 RPM. *TT

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

Engine, Exhaust and emissions

Vehicles listed
CHEVROLET ASTRO1996 to 2001
CHEVROLET BLAZER1996, 1997, 1998, 1999, 2000, 2001
CHEVROLET ENVOY1996
CHEVROLET EXPRESS1996
CHEVROLET EXPRESS1997, 1998, 1999, 2000, 2001
GMC ENVOY1997 to 2001
GMC JIMMY1996 to 2001
GMC SAFARI1996, 1997, 1998, 1999, 2000, 2001
GMC SAVANA1996, 1997, 1998, 1999, 2000, 2001
OLDSMOBILE BRAVADA1996, 1997, 1998, 1999, 2000, 2001

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

Recalls for the same vehicles and component
19980401998-03-18. Emissions
19972161997-11-28. Emissions
19970041997-01-14. Emissions

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
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.
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.
16-NA-3832024-07-16. Service bulletin. This service bulletin advises of a new fuel injection cleaner kit used for decarbonizing the intake valves to correct conditions of rough idle, Crank no start, extended crank or misfire, MIL with DTCs, and explains how Top Tier fuels should be used to reduce carbon build-up.
16-NA-3832024-03-19. Service bulletin. This technical bulletin advises of a new fuel injection cleaner kit used for decarbonizing the intake valves to correct conditions of rough idle, Crank no start, extended crank or misfire, MIL with DTCs, and explains how Top Tier fuels should be used to reduce carbon build-up.
06-06-01-019C2024-03-19. Service bulletin. This bulletin advises the technician of possible location of an internal coolant leak from a specific cylinder head and location.
22-NA-0742024-02-29. Service bulletin. This service bulletin provides service information to technicians on guidelines to replace Oil Cooler, Oil Cooler Lines and Oil Tank if the engine was replaced where large amounts of debris has flowed throughout the oiling system.
PI1394B2024-02-02. Service bulletin. This PI bulletin advises the technician on the proper way to install the pistons in an engine.
1300890092023-12-11. Service bulletin. Expanded Availability for Remanufacture and Return (R&R) Electronic Control Modules
23-NA-1532023-09-26. 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.
PIP5628G2023-09-18. Service bulletin. This Preliminary information communicates information that will need to be provided to TAC to aid in diagnosing if a vehicle comes in with misfire and DTC Codes P0300 - P0308 and/or P050D