I always stop into the Dollar store. I trust the dollar store and never would have thought about this according to  New York State may have purchased expired products, including obsolete motor oil and over-the-counter medications that were past their use-by date.

The New York State Attorney General's Office just released the results of an undercover investigation into Dollar General, Dollar Tree and Family Dollar stores.

The AG's Office conducted a number of visits to the stores beginning in March 2016, and found that all three retail chains stocked medications that were often months beyond their expiration date. The investigation also revealed that some motor oil sold by Dollar General was not suitable for most cars built after 1930"

If you purchased motor oil from the Dollar General, you are able to file a complaint.  You can find a link to make a complaint about the motor oil here.