Jeep has dominated the American 4x4 market with its famous Wrangler for nearly three decades, and given how the “Big Three” American automakers love to compete with each other, it's clear that neither Ford nor General Motors were happy about seeing this action from the sidelines. As a result, Ford has decided to step into the fighting ring by reviving its Bronco off-road SUV, but Chevy went the other direction with a sportier and rather suburban Blazer. But if any recent Jeep Wrangler sightings are to be believed, GM might be up to something at its Milford Proving Grounds in Michigan.

Photos recently shared by GMAuthority show engineers from the General benchmarking some test mules with a pair of four-door Wrangler models. This is apparently the first time GM has ever used a Wrangler as a benchmark for testing SUVs in at least the past decade. Although far from a confirmation, the fact that GM is using a Wrangler as a benchmark is a major hint that a Wrangler competitor is indeed in the works.