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Service bulletins for the 2003 GMC Envoy

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.

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

By type

By component

By trouble code

Only bulletins with component: Transfer case are shown. Show all

Bulletins, newest first
PIP3366C2018-08-20. Service bulletin. POWER TRAIN:TRANSFER CASE (4-WHEEL DRIVE); POWER TRAIN:AUTOMATIC TRANSMISSION. This Preliminary information communicates to the dealer technician thatLight Duty Trucks equipped with automatic transmissions and 4 wheel drive may exhibit a condition of grinding/ratcheting type noise when shifting the automatic transmission into park while the transfer case is in 4 wheel drive low (4LO) range. Dealers technician's are advised this condition should be deemed a normal characteristic of 4WD low operation.
05-04-21-0032005-11-09. Service bulletin. POWER TRAIN:TRANSFER CASE (4-WHEEL DRIVE). SERVICE 4WD LIGHT ILLUMINATED, DIAGNOSTIC TROUBLE CODE (DTC) C0374 SET. *TT UPDATED 10/05/07. *NJ INSPECT WIRING HARNESS TO TRANSFER CASE SPEED SENSORS, REPLACE WIRING HARNESS. UPDATED 7/18/08 *PE
0404210042005-11-08. Service bulletin. POWER TRAIN:TRANSFER CASE (4-WHEEL DRIVE). 4WD SWITCH INDICATOR LIGHTS FLASHING, 4WD INOPERATIVE, DIAGNOSTIC TROUBLE CODES C0327, P0550 SET. *TT
34242005-11-02. Service bulletin. POWER TRAIN:TRANSFER CASE (4-WHEEL DRIVE). ELECTRONIC TRANSFER CASE UNABLE TO COMPLETE SHIFT. *TT
33512005-05-11. Service bulletin. POWER TRAIN:TRANSFER CASE (4-WHEEL DRIVE). INTERMITTENT MALFUNCTION INDICATOR LAMP (MIL) WITH DIAGNOSTIC TROUBLE CODE (DTC) C0374 OR ERRATIC 4WD/AWD OPERATION. *TT
091320022004-09-30. Service bulletin. POWER TRAIN:TRANSFER CASE (4-WHEEL DRIVE). THIS MESSAGE COVERS COMMENTS THAT THE SERVICE FOUR-WHEEL DRIVE INDICATOR IS ILLUMINATED OR FOUR-WHEEL DRIVE IS INOPERABLE. *TT
018432004-07-19. Service bulletin. POWER TRAIN:TRANSFER CASE (4-WHEEL DRIVE). CALIBRATION FOR IMPROVED TRANSFER CASE OPERATION IN AWD MODE. *TT
020421006C2003-12-04. Service bulletin. POWER TRAIN:TRANSFER CASE (4-WHEEL DRIVE). INOPERATIVE 4WD/AWD LAMPS, INOPERATIVE 4WD/AWD SYSTEM. *TT
01446A2003-11-24. Service bulletin. POWER TRAIN:TRANSFER CASE (4-WHEEL DRIVE). SERVICE 4WD LIGHT ON NO CODES BESIDES U1000 CODES. *TT
020421002A2003-04-17. Service bulletin. POWER TRAIN:TRANSFER CASE (4-WHEEL DRIVE). SERVICE 4WD INDICATOR ILLUMINATED, DIAGNOSTIC TROUBLE CODE (DTC) B2725 SET, TRANSFER CASE SELECTOR SWITCH IS IN ONE POSITION - INDICATOR LAMP INDICATES ANOTHER RANGE IS SELECTED. *TT
020421006A2003-02-14. Service bulletin. POWER TRAIN:TRANSFER CASE (4-WHEEL DRIVE). INOPERATIVE 4WD/AWD LAMPS, INOPERATIVE 4WD/AWD SYSTEM. *TT

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