For used inventory, yes.
Captive lenders are captive to the dealer and can finance anything that dealer can sell.
Of course, incentives like 0% financing or cash back or any of that kind of thing only applies to new cars, but for a straight loan on a used car purchased from the dealer, the captive lenders will consider it just like any other lender would.
Many dealers work with more than one lender anyway - that is, a Chevy dealer may use Ally (their captive, used to be called GMAC) and Chase and WFDS and others concurrently; most also have a small army of credit unions and other lenders on speed dial as well. When a dealer finance office runs your application, it is common for them to shop a dozen lenders at once, not just their branded captive.
