I worked in a Chrysler -Plymouth dealership when I went to college. Sales traded in an Audi that a young couple owned that had two St. Bernards. That rode in the back seat. A lot. The stench from those dogs was unbearable. The kid that was on the wash rack and I tried everything we could think of and could never get the smell completely out. We told the boss it'd take new upholstery to get rid of it and when he saw what that cost, the car got sold at a substantial loss.