Mercedes-AMG CLE 63 Prototype Hits the Alps - With a Trailer in Tow

Picture this: You’re behind the wheel of a V8-powered Mercedes-AMG CLE coupe, carving through the Austrian Alps. Sounds like a dream, right? Now imagine hooking up an 1,800-pound dual-axle trailer and running braking and cooling tests on tight mountain roads. That’s exactly what CarBuzz spy photographers caught Mercedes doing with the upcoming CLE 63 prototype.

0-liter twin-turbo V8 through its paces, ensuring the big rotors and multi-piston calipers can handle the heat, literally.

0-liter inline-six hybrid. 0-liter beyond anything we’ve seen from it. On the outside, expect subtle updates: new headlights featuring Mercedes’ star logo, a reshaped grille, and larger lower intakes to feed that hungry V8. Inside, the dash display looks wider, the center screen likely runs an updated operating system, and the steering wheel swaps haptic controls for real buttons, a nod to driver feedback.

Testing like this is one of the final hurdles before the CLE’s official reveal. Mercedes is dialing in braking, cooling, and system calibrations beyond what simulations can achieve. Combine this with teaser photos of the Mythos and the time since we first spotted the CLE prototype, and it’s clear the car is nearly ready.

Why does this matter? Mercedes-AMG had shifted to smaller four-cylinder and six-cylinder engines with hybrids to meet emissions standards, but buyers pushed back hard. The company listened, admitting downsizing drove customers away. Now the big V8 is back, and Mercedes has designed a new one.