New Shelby GT500 in the works?

It seems Ford is gearing up for the return of the Shelby badge on its new Mustang, as several heavily disguised prototypes have been spotted near the company’s Dearborn, Michigan, headquarters—signalling the early stages of testing for the new Shelby GT500.

The test mules are based on the Mustang Dark Horse, the current top-tier performance model introduced with the seventh-generation Mustang in 2024. These prototypes sport a number of modifications that hint at something far more potent lurking beneath the surface.

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The most obvious changes are up front. The prototypes feature a reworked fascia with enlarged air intakes and prominent radiators, suggesting the need for additional cooling—likely due to a powerful new engine. The front wheel arches are also subtly reshaped, seemingly to accommodate wider tires, while camouflage at the rear hints at further performance upgrades yet to be revealed.

Adding to the intrigue are the wheels: the mules are rolling on either the last-gen GT500’s standard wheels or the ultra-lightweight 20-inch carbon-fibre wheels from the Carbon Fiber Track Package. Tyre choices vary, with some cars shod in Michelin Pilot Sport Cup 2 R rubber, and others in Pirelli P Zero R tyres—both upgrades over the Dark Horse’s standard P Zero Trofeo RS setup.

Interestingly, Ford engineers have included a cheeky decal on the front fenders—a cartoon mule kicking its hind legs—marking these as official test vehicles.

The timing of these sightings aligns with a rumoured internal memo from the United Auto Workers union, which leaked online last month before being swiftly deleted. According to the document, the Dearborn Engine Plant will begin building a new engine for the 2026 Shelby GT500, referred to by the codename “Legend.” While Ford hasn’t confirmed details, this engine is expected to at least match—if not exceed—the previous GT500’s monstrous 560kW and 850Nm figures from its 5.2-litre supercharged V8.

Though the test cars still resemble the current Dark Horse in many areas, the production version of the new Shelby GT500 is likely to receive further styling tweaks, including a revised grille, unique hood, and aggressive aerodynamic add-ons befitting its performance pedigree.

Expect the new Shelby GT500 to make its official debut sometime ahead of its anticipated 2026 arrival—bringing back a legendary name with what could be the most powerful road-going Mustang yet.