Yes, Chevy is still doing pretty good in North America (USA / Canada). It is also one of the top sellers in other countries from South America, such as Brazil and Argentina.
The trucks (or pick ups) from Chevrolet are quite famous and reliable. They have atractive prices and can be found wherever you look when you are either in the USA/Canada.
The brand is not falling or having trouble selling its cars/trucks in the US or Canada.
So the final answer to your question is yes, it is still a pretty solid brand in America.