Automakers regularly test a variety of vehicles on the open road. Sometimes its easy to tell what they’re working on – at other times, less so.

These latest spy shots, snapped by eagle-eyed reader Brett Borgard, show a motorcade of Ford Mustangs testing in the high altitudes of Colorado. The manufacturer plates tell us who’s running them. But just what are they testing, exactly?

There’s three of them to be seen, all ostensibly of the newly updated 2018 model (judging primarily from their auxiliary front LED lighting strips): one in white, one all murdered out in black, and another in a dark shade of burgundy that looks like Ford’s Royal Crimson option.

While the burgundy and black examples give us little to go on – especially viewed from the front – the white Mustang GT is seen sporting a pair of extended exhaust tips protruding out from under the bumper, and labels reading “Caution: Fuel Drain.”

The trio could be testing for emissions or trying out some new equipment. Only a few engineers and product planners in Dearborn likely know for sure. But you can bet they’ve got some new versions of the pony car in the works.

 Tip of the hat to Brett!

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