Eminem's ride or die for his home state, but not when it comes to a Ford dealership in Michigan using his biggest hit to sell limited edition trucks.

Em fired off the lawsuit Monday against LaFontaine Ford St. Clair -- which owns multiple car dealerships -- over an online ad it started running last fall to promote a limited edition Detroit Lions Ford F-150 pickup truck.

The ad is not only scored with "Lose Yourself," but it also features a caption that reads, "You only get one shot to own a Special Edition Detroit Lions F-150."

Clever, and maybe they thought a huge Lions fan like Eminem would let it slide, but to quote the man himself, "Snap back to reality" ... he's not giving it away.

In the suit, filed in federal court by Em's company Eight Mile Style, they say the Oscar-winning hit is extremely valuable, which they know because it was previously licensed to Chrysler for a 2011 Super Bowl ad.

Em's attorneys say legal usage of the song generated millions in sales for Chrysler ... so, they're certainly not giving the Ford dealer a free ride.

They're asking a judge to award monetary damages, and want the dealership to pull the ad immediately or risk losing itself ... in court.

We've reached out to LaFontaine Ford St. Clair ... so far, no word back.