QOTD: What's An SUV?

Hoo boy, day three and we’re already into the dumbest, most annoying kind of question, the one that really doesn’t have an answer. But, here we go: What’s an SUV, as opposed to a crossover? It came up today for the 754th time in my career when Norman asked where I’d classify the new MDX. I said crossover. It’s unibody and has fully independent suspension.

Problem is, by that standard, the Land Rover Defender and Jeep Grand Cherokee are also crossovers, while the above Bronco, the Jeep Wrangler, Lexus GX and Toyota 4Runner are SUVs. What about the new Escalade? Where do you personally draw the line?