Even the best Puzzle Masters make an occasional mistake. But Martin Gardner and Will Shortz probably never had one of their errors exposed as dramatically (and hilariously) as Ray’s recent mango tree Puzzler. Find out how it plays out, this week on the Best of Car Talk. Elsewhere, Robert’s Mercedes dealer gave him a blanket and pen to apologize for over-filling his engine with oil. Should Robert have asked them to wrap a new engine in that blanket? Also, Carey thinks her husband’s downshifting advice may be responsible for her Expedition’s clunk, but the noise may have more to do with the 9,000 pounds of barbecue equipment Carey is hauling around; and, a tale of what happens when overly-encumbered by the thought process engineers try to paint an apartment. All this and more, this week on The Best of Car Talk.