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Service bulletins for the 1999 GMC Sonoma

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.

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

By type

By component

By trouble code

Bulletins, newest first
PIC4696A2017-08-15. Service bulletin. EQUIPMENT:ELECTRICAL:ANTI-THEFT DEVICES; EQUIPMENT:ELECTRICAL:RADIO/TAPE DECK/CD ETC.. This Preliminary Information communication provides information to the technician on how to unlock radios that are Delco TheftLock. Technician will use the radio to get the scrambled code. Technician will need to contact the radio unlock center to retrieve the unlock code from the scrambled code.
PIP53402017-08-15. Service bulletin. POWER TRAIN. This Preliminary Information communication provides information to the technician about vehicle that after a transmission or torque converter replacement the vehicle may have a harsh 1-2 upshift and the Check Engine Light or Service Engine Soon indicator is illuminated. If you have duplicated the customer?s concern and found Diagnostic Trouble Code P0894 or P1870 set in the Transmission Control Module please contact General Motors Technical Assistance Center.
PIT3227L2017-08-15. Service bulletin. STRUCTURE:BODY:TAILGATE:HINGE AND ATTACHMENTS. This Preliminary Information communication provides information to the technician about vehicles that may have slack in one of the tailgate cables. Technician should not replace any parts for this concern. Please communicate to the customer this condition is a normal operating characteristic of their vehicle.
PIT3227K2017-08-15. Service bulletin. STRUCTURE:BODY:TAILGATE. This Preliminary Information communication provides information to the technician about vehicles that may have slack in one of the tailgate cables. Technician should not replace any parts for this concern. Please communicate to the customer this condition is a normal operating characteristic of their vehicle.
PIP4723B2017-08-15. Service bulletin. ELECTRICAL SYSTEM:SOFTWARE. This Preliminary Information communicates to the dealer the process for downloading or updating operating software for the Tire Pressure Monitor, Active Fuel Injector tester, multi media tester, PICO Scope, GR8 starting/charging tester and Vehicle Data Recorder tools, giving website address and step by step instructions to complete the update.
PIT3227M2017-08-15. Service bulletin. STRUCTURE:BODY:TAILGATE. This Preliminary Information communication provides information to the technician about vehicles that may have slack in one of the tailgate cables. Technician should not replace any parts for this concern. Please communicate to the customer this condition is a normal operating characteristic of their vehicle.
PIT3227H2017-08-15. Service bulletin. STRUCTURE:BODY:TAILGATE. This Preliminary Information communication provides information to the technician about vehicles that may have slack in one of the tailgate cables. Technician should not replace any parts for this concern. Please communicate to the customer this condition is a normal operating characteristic of their vehicle.
PIP3720D2017-08-15. Service bulletin. POWER TRAIN:AXLE ASSEMBLY. This Preliminary Information communication provides information to the technician with the axel setup information from American Axle Manufacturing. Technician should be advised that the maximum pinion shim to be used or stacked behind the pinion is 0.050?, and the minimum pinion shim is 0.020? for an 8.6 axle. The range for available pinion depth shims for the 10.5? axle is 0.006? to 0.024?. When setting the backlash it should be set between 0.003? to 0.005? on a new ring and pinion for any American Axle Manufacturing application. The ring and pinion can be reused or adjusted if the mileage is less than 500 miles, if not used for towing. Technician should be advised that a ?roller coaster? or ?hourglass? pattern on the bearings may be normal up to 10,000 miles and possibly longer. With a mis-machined housing you may get a heel pattern on both sides of the gear teeth at build up can generally be corrected with backlash adjustments. When setting up an 8.6? axle with a 5 cut gear set is to use a 0.035? pinion shim and set backlash to 0.004?. When using the newer 2 cut gear set also use a 0.035? pinion shim and still set backlash to 0.004?. To set the gear pattern use backlash to adjust the pattern heel to toe. Use the pinion shim to adjust the height of the pattern. The proper drive pinion bearing pre-load is from 15 - 30 inch pounds with new bearings. The total torque to turn after the differential case is installed should increase 5 - 10 inch pounds at the pinion. A new pinion nut must be used whenever the old one is removed. The axle shaft end play specification is 0.012? per side and the radial specification is 0.002? - 0.003?. Technician should be advised that synthetic lube can be used in all new American Axle Manufacturing axle assemblies. The new pinion seal for the 8.6? axle assembly is a two piece design.
PIT3227J2017-08-15. Service bulletin. STRUCTURE:BODY:TAILGATE:HINGE AND ATTACHMENTS; STRUCTURE:BODY:TAILGATE. This Preliminary Information communication provides information to the technician about vehicles that may have slack in one of the tailgate cables. Technician should not replace any parts for this concern. Please communicate to the customer this condition is a normal operating characteristic of their vehicle.
PIP5340A2017-03-21. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION:TORQUE CONVERTER. THIS PRELIMINARY INFORMATION COMMUNICATION PROVIDES INFORMATION TO THE TECHNICIAN ABOUT VEHICLE THAT AFTER A TRANSMISSION OR TORQUE CONVERTER REPLACEMENT THE VEHICLE MAY HAVE A HARSH 1-2 UPSHIFT AND THE CHECK ENGINE LIGHT OR SERVICE ENGINE SOON INDICATOR IS ILLUMINATED. IF YOU HAVE DUPLICATED THE CUSTOMER’S CONCERN AND FOUND DIAGNOSTIC TROUBLE CODE P0894 OR P1870 SET IN THE TRANSMISSION CONTROL MODULE PLEASE CONTACT GENERAL MOTORS TECHNICAL ASSISTANCE CENTER.
16NA2602016-10-17. Service bulletin. EQUIPMENT:ELECTRICAL:RADIO/TAPE DECK/CD ETC.. THIS TECHNICAL BULLETIN PROVIDES A PROCEDURE TO REPROGRAM THE MEDIA DISC PLAYER WITH THE LATEST CALIBRATIONS TO CORRECT A CONDITION OF THE REAR ENTERTAINMENT SYSTEM NOT OPERATING AS INTENDED IN COLDER AMBIENT TEMPERATURE AREAS DUE TO CALIBRATION CONCERNS.
PIP-3366-B2012-02-29. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION. CADILLAC/CHEVROLET/GMC/HUMMER: SOME SUVS AND TRUCKS ARE EXHIBITING A CONDITION WHERE BY GRINDING/RATCHETING TYPE NOISE COMING FROM AUTOMATIC TRANSMISSION WHEN SHIFTING INTO PARK WHILE IN 4WD LOW (4LO) RANGE. *PE
41142006-10-23. Service bulletin. STRUCTURE:BODY. CLUNK NOISE FELT THROUGH THE FLOOR PAN. *KB
37772006-01-06. Service bulletin. ELECTRICAL SYSTEM. FUEL AND TEMPERATURE GAUGE INOPERATIVE, LOW FUEL AND BATTERY LIGHT ON, PRNDL INOPERATIVE. *TT
007732005-10-27. Service bulletin. POWER TRAIN. 4L60E, 4L65E REPLACEMENT VALVE BODY GASKETS DOES NOT SEEM TO FIT. *TT
3170B2005-10-27. Service bulletin. ELECTRICAL SYSTEM. INSTRUMENT PANEL CLUSTER INTERIOR AND/OR HEAD LAMPS FLICKER. *TT
572005-09-14. Service bulletin. STRUCTURE:BODY. WATER LEAK IN FRONT FLOOR CARPET AREA. GM TECH LINK. *TT
33002005-04-21. Service bulletin. POWER TRAIN:DRIVELINE. 4WD MODELS WITH NOISE, VIBRATION ON DRY PAVEMENT. *EH
33592005-04-21. Service bulletin. ELECTRICAL SYSTEM. INTERIOR LIGHTS INOPERATIVE AFTER BCM REPLACEMENT B2618 DIAGNOSTIC TROUBLE CODE. *TT
0406030022005-03-11. Service bulletin. ENGINE AND ENGINE COOLING. DIAGNOSTIC INFORMATION FOR INTERMITTENT VEHICLE NO CRANK DEAD BATTERY. *EH
32272005-01-31. Service bulletin. STRUCTURE:BODY:TAILGATE. TAILGATE CABLE SLACK. THIS INCLUDES 1998-2006 CHEVROLET AND GMC FULL AND MID SIZE TRUCKS. *EH UPDATED. *KB
30812004-11-17. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE. SERVICE ENGINE SOON LIGHT AND P0300 WHEN TOWING, CRUISING UPHILL OR ON HARD ACCELERATION. *TT
3176A2004-11-09. Service bulletin. EQUIPMENT:APPLIANCE:AIR CONDITIONER. HEAT COMING FROM VENTS WITH HVAC OFF. *TT
3170C2004-11-05. Service bulletin. EXTERIOR LIGHTING:HEADLIGHTS. INSTRUMENT PANEL CLUSTER (IPC) INTERIOR AND/OR HEAD LAMPS FLICKER. *TC
31302004-11-04. Service bulletin. ELECTRICAL SYSTEM. INSTRUMENT CLUSTER PRNDL INOPERATIVE AND OR BATTERY LIGHT ON. *SC

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