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Service bulletin GCUS-3-778

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 id10125996
Published by NHTSA2017-12-22
Manufacturer's numberGCUS-3-778
Manufacturer's date2016-12-05
NHTSA componentELECTRICAL SYSTEM; POWER TRAIN

NHTSA's summary

16159 Service Update. On certain vehicles with an 8-speed transmission (MRC), under certain downhill driving conditions, these vehicles may inappropriately remain in a mode of delayed upshifts that can only be exited on an ignition key cycle or gear selector shift to neutral. Dealers are to reprogram the transmission control module.

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

Electrical system, Transmission and driveline

Vehicles listed
BUICK LACROSSE2017

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

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08-07-30-035I2024-12-19. Service bulletin. This service bulletin provides information on the harmful effects of ethylene glycol in transmission fluid.