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Service bulletin 17426 (Bulletin

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 id10135148
Published by NHTSA2018-05-07
Manufacturer's number17426 (Bulletin
Manufacturer's date2017-11-09
NHTSA componentPOWER TRAIN:AUTOMATIC TRANSMISSION:TORQUE CONVERTER

NHTSA's summary

17426 - Service Update. Certain vehicles, equipped with the manual shift transfer case (RPO NQG), may have a condition in which the transfer case shift linkage rod bolt torque is less than specified. Over time this bolt could loosen enough to allow the transfer case shift indicator to be inaccurate; or the bolt could fall off causing the transfer case to remain in its previous position and the shifter to be non-functional. Tighten the transfer case shift linkage rod bolt to the specified torque.

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, Automatic transmission, Torque converter

Vehicles listed
CHEVROLET SILVERADO 25002018 (the catalog's model; the bulletin names a series or trim of it)

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

Other bulletins for the same vehicles and component
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990420002L2021-08-09. Service bulletin. This service bulletin provides information on Driveline Clunk Noise and what is acceptable and what is considered normal operation.
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