Thanks for the info,I just ran across this tonight and its good to know everything about my RexService Bulletin, 17-NA-376: 2018 Buick Regal New Model Features, is a special bulletin to introduce the 2018+ Regal GS, Sportback, and TourX models. The purpose of this bulletin is to help the Service Department Personnel become familiar with some of the vehicle’s new features and capabilities.
It contains a lot of information that isn't stated in our manuals or is difficult to find online. Covered in this bulletin are detailed descriptions of the engine, transmission, infotainment, cluster, tires, sound insulation, and safety technologies. Some of this information is nothing new for longtime owners, but it is invaluable for new owners or prospective buyers.
The bulletin is attached as a PDF and also linked on the NHTSA website.