Crude Oil—Private-label motor oil sold at Dollar General stores is more suitable for a Ford Model T than for modern-day cars, according to a putative class action filed against the retailer in federal court in Camden.

Dollar General motor oils state in fine print on the 10W-30 and 10W-40 varieties that they are “not suitable for use in most gasoline-powered automotive engines made after 1988,” while the SAE 30 variety states that it “not suitable for use in most gasoline powered motored engines built after 1930.”