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Service bulletin 14121B

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 id10247322
Published by NHTSA2023-12-18
Manufacturer's number14121B
Manufacturer's date2014-05-01
NHTSA componentPOWER TRAIN

NHTSA's summary

Transmission Oil Cooler Connection

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

Transmission and driveline

Vehicles listed
CHEVROLET SILVERADO 15002014 (the catalog's model; the bulletin names a series or trim of it)
CHEVROLET SILVERADO 25002014 (the catalog's model; the bulletin names a series or trim of it)
CHEVROLET SILVERADO 35002014 (the catalog's model; the bulletin names a series or trim of it)
CHEVROLET SUBURBAN2015
CHEVROLET TAHOE2015
GMC SIERRA 15002014 (the catalog's model; the bulletin names a series or trim of it)
GMC SIERRA 25002014 (the catalog's model; the bulletin names a series or trim of it)
GMC SIERRA 35002014 (the catalog's model; the bulletin names a series or trim of it)
GMC YUKON2015
GMC YUKON XL2015

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

Recalls for the same vehicles and component
26V2890002026-05-07. POWER TRAIN:TRANSFER CASE (4-WHEEL DRIVE)
20142542014-06-27. Powertrain
14V3740002014-06-27. POWER TRAIN:TRANSFER CASE (4-WHEEL DRIVE)
20141022014-03-31. Powertrain
14V1520002014-03-31. POWER TRAIN:AUTOMATIC TRANSMISSION:COOLING UNIT AND LINES
20134562013-12-20. Powertrain

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
PI0281L2025-06-12. Service bulletin. This preliminary informational (PI) bulletin provides information to dealership personnel that may be helpful when addressing underbody component corrosion with customers.
PIP5966A2025-03-02. Service bulletin. This Preliminary information communicates Diagnostic aids for a no start or DTC'S following a transmission replacement
PIP5966A2025-03-02. Service bulletin. This Preliminary information communicates Diagnostic aids for a no start or DTC'S following a transmission replacement
16-NA-0192025-02-19. Service bulletin. This service bulletin provides information on Transmission Adaptive Functions and Correcting Low Mileage Harsh Shifts, Slips, or Flares.
PIP5175F2025-02-10. Service bulletin. This Preliminary Information communication provides information to the technician about vehicles that may have a delayed engagement into drive, shudder at a launch, or the transmission is slipping when shifting into 1st, 2nd, 3rd or 4th gears. This may be due to loose stator support to pump cover bolts causing a leak at the stator support to pump cover gasket. Technician will check for the bolts to be loose. If any of the bolts are loose or the gasket is misaligned or leaking, the transmission pump cover must be replaced and the 1234 clutch plates should be inspected for being distressed and repaired as needed.
09-06-04-026Z2025-01-23. Service bulletin. This bulletin provides information on identifying Non-GM Engine Calibrations for Gasoline Engines using the Tech 2 or GDS 2.
08-07-30-035I2024-12-19. Service bulletin. This service bulletin provides information on the harmful effects of ethylene glycol in transmission fluid.
PIP60142024-12-05. Service bulletin. This Preliminary information communicates for Technicians installing a Service Replacement Transmission Assembly to contact Technical Assistance to make sure unit is not suspect of a snap ring concern prior to installation.
04-06-01-029K2024-12-04. Service bulletin. This informational bulletin explains Unscheduled Supplemental Services and the importance of GM Simplified Maintenance Schedules.
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.