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Service bulletins for the 2018 GMC Savana

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.

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

By type

By component

By trouble code

By topic

Only bulletins with component: Transmission and driveline are shown. Show all

Bulletins, newest first
990420002L2021-08-09. Service bulletin. POWER TRAIN:MANUAL TRANSMISSION; POWER TRAIN:AUTOMATIC TRANSMISSION; EQUIPMENT. This service bulletin provides information on Driveline Clunk Noise and what is acceptable and what is considered normal operation.
080730035E2021-08-09. Service bulletin. EQUIPMENT; EQUIPMENT ADAPTIVE/MOBILITY; POWER TRAIN. This bulletin provides information on the harmful effects of water or ethylene glycol in transmission fluid.
PIP5621B2021-06-14. Service bulletin. POWER TRAIN. This Preliminary information communicates to the dealer technician that TAC recommends the utilization of the GDS2 software to aid in diagnosing automatic transmission concerns. TAC is requesting the GDS2 session logs be sent in before the dealer contacts TAC.
16NA3382021-05-24. Service bulletin. POWER TRAIN. This Warranty Admin service bulletin provides guidelines for Dealers Not Required and for Dealers Required to Contact the PQC for engine or transmission assembly replacement and explains the PQC process, GWM Transaction submission, vehicle service record retention and proper handling of assembly returns for Canadian Dealers only.
PIP58002021-05-17. Service bulletin. POWER TRAIN; EQUIPMENT. This Preliminary information communicates some customers may comment that the vehicle exhibits a lack of power when driving up grades or after the vehicle has been idling for long periods of time in high ambient temperatures (90 degrees or above). This condition is more noticeable when the vehicle is outfitted with heavy work equipment on the back such as work boxes or ambulance bodies. When the ambient temperature drops below 90 degrees you may notice that the condition is less noticeable or eliminated altogether. This condition is caused by the high ambient temperatures 90 degrees effecting the intake air flow to the engine
20NA1382021-05-03. Service bulletin. ENGINE AND ENGINE COOLING; POWER TRAIN. 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.
150089004C2021-03-08. Service bulletin. SUSPENSION:FRONT:MACPHERSON STRUT; SUSPENSION:FRONT:SHOCK ABSORBER; POWER TRAIN:AUTOMATIC TRANSMISSION:FLUID/LUBRICANT. This service bulletin provides technicians with updated information to help identify the differences between what is considered a fluid leak, and what is considered fluid seepage.
20NA1422021-03-01. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL; POWER TRAIN:AUTOMATIC TRANSMISSION:TORQUE CONVERTER. This Technical bulletin provides a repair to correct a condition of Shudder/Surging While Driving.
19NA1532021-02-22. Service bulletin. POWER TRAIN. This technical bulletin provides a procedure to replace the torque converter and inspect the front pump and the TEHCM for metal.
16NA0192021-02-22. Service bulletin. POWER TRAIN. This informational bulletin provides information on Transmission Adaptive Functions and Correcting Low Mileage Harsh Shifts, Slips, or Flares.
19NA1532021-02-01. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION:TORQUE CONVERTER. This technical bulletin provides a procedure to replace the torque converter and inspect the front pump and the TEHCM for metal.
16NA0192021-02-01. Service bulletin. POWER TRAIN; ELECTRICAL SYSTEM:SOFTWARE. This informational bulletin provides information on Transmission Adaptive Functions and Correcting Low Mileage Harsh Shifts, Slips, or Flares.
060089031F2020-12-21. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION; ENGINE. This service bulletin provides information on OEM and Remanufactured Engine and Automatic Transmission/Transaxle Identification.
20NA1422020-12-21. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION; EQUIPMENT; EQUIPMENT ADAPTIVE/MOBILITY. This Technical bulletin provides a repair to correct a condition of Shudder/Surging While Driving.
1308116001F2020-12-07. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM; POWER TRAIN:AUTOMATIC TRANSMISSION. The intent of this technical bulletin is to identify aftermarket ALDL or DLC interface devices as potential sources for causing multiple customer concerns that do not have other diagnostic methods to identify them.
20NA1422020-11-30. Service bulletin. EQUIPMENT; POWER TRAIN:AUTOMATIC TRANSMISSION:TORQUE CONVERTER. This Technical bulletin provides a repair to correct a condition of Shudder/Surging While Driving.
20NA1872020-10-26. Service bulletin. POWER TRAIN. This technical bulletin provides a repair procedure to correct a customer concern of Delayed and/or Harsh Engagement of Transmission Shift After Vehicle Sitting with Engine Off.
20NA1422020-10-26. Service bulletin. EQUIPMENT; POWER TRAIN:AUTOMATIC TRANSMISSION:FLUID/LUBRICANT. This Technical bulletin provides a repair to correct a condition of Shudder/Surging While Driving.
16NA0192020-10-26. Service bulletin. POWER TRAIN. This informational bulletin provides information on Transmission Adaptive Functions and Correcting Low Mileage Harsh Shifts, Slips, or Flares.
16NA3612020-09-28. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION. This informational bulletin explains possible normal condition of a flare from 1st to 2nd, even if the trans had been repaired for the flare and its still noticed.
20NA1422020-08-31. Service bulletin. POWER TRAIN. This Technical bulletin provides a repair to correct a condition of Shudder/Surging While Driving.
16NA3382020-08-31. Service bulletin. ENGINE; POWER TRAIN. This Bulletin provides guidelines for Dealers Not Required and for Dealers Required to Contact the PQC for engine or transmission assembly replacement and explains the PQC process, GWM Transaction submission, vehicle service record retention and proper handling of assembly returns for Canadian Dealers only.
PIP5504F2020-08-10. Service bulletin. ENGINE; POWER TRAIN. This Preliminary Information communication provides information and definitions to the technician about vehicles that have fishbite, chuggle, misfire, AFM disturbances or torque converter shudder/vibration concerns. Technician are advised to use PICO software to determine root cause of the concern. If torque converter shudder is confirmed technicians are referred to Torque Converter Diagnosis in SI.
PIP5504E2020-08-10. Service bulletin. POWER TRAIN. This Preliminary Information communication provides information and definitions to the technician about vehicles that have fishbite, chuggle, misfire, AFM disturbances or torque converter shudder/vibration concerns. Technician are advised to use PICO software to determine root cause of the concern. If torque converter shudder is confirmed technicians are referred to Torque Converter Diagnosis in SI.
PIT5206G2020-08-10. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; ELECTRICAL SYSTEM; POWER TRAIN:AUTOMATIC TRANSMISSION; SERVICE BRAKES; EQUIPMENT. This Preliminary Information communication provides information to the technician with the steps on diagnosing and repairing vehicles that may have unwanted grade braking, reduced engine power with no Driver Information Center messages ? Brake Pedal Override Feature ?, transmission busy or frequent shifting up or down, and Diagnostic Trouble Codes P057B, P057C, and/or P057D may or may not be set. Technician will use this preliminary information to find the brake pedal position data parameters in the scan tool, and also to provide some additional diagnostic help. These issues may be caused by an incorrect brake pedal position sensor input to the engine control module. Technician will verify with the scan tool if the engine control module has the correct parameters for the brake pedal position sensor. If an engine control module brake pedal position sensor relearn is performed, the truck may be temporarily repaired until the intermittent wiring issue between the engine control module and brake pedal position sensor occurs again. On 2014 and newer trucks inspect and repair any damage to X115 and X119. On the 2014 and previous trucks inspect and repair any damage to X205.

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