- GLE 63 S Coupe and GLS 63 SUVs get a new flat-plane crankshaft V8.
- The 603-horsepower twin-turbo V8 rating remains the same, but Mercedes predicts a boost in efficiency.
- New color choices and wheel designs, along with a new grille design, complement the engine and exhaust updates.
Mercedes is keeping its hands on the pulse of its iconic AMG V8. The updated 2027 Mercedes-AMG GLE 63 S and GLS 63 performance SUVs debut with a new handcrafted 4.0-liter twin-turbo V8 designed with a flat-plane crankshaft, among several other mechanical updates that Mercedes-AMG showed off on Monday.
The flat-plane design replaces the more conventional cross-plane crank in the performance SUVs’ predecessors, promising more responsiveness to throttle inputs and quicker, smoother revving. The further investment in the AMG performance division’s legendary V8 comes after years of questions about its future due to more stringent global emissions regulations that have since been relaxed in the U.S., which is one of Mercedes’ more lucrative markets.
“Our V8 is a central component of our performance DNA and the ideal heart for the new GLE 63 S and GLS 63,” Michael Schiebe, Member of the Board of Management of Mercedes‑Benz Group AG, said in a statement. “The result is an engine that impresses with agile response, strong performance, and a pronounced appetite for revs — while at the same time meeting increasingly demanding regulations worldwide.”
To hush the haters, Mercedes said the flat-plane design will still offer the same level of refinement expected in Mercedes’ 6-figure luxury lineup, and other changes to the exhaust, injection, and turbo systems should increase efficiency beyond the 17 mpg combined achieved by the 2026 Mercedes-AMG GLE 63 S.
What’s New for the 2027 AMG GLE and GLS 63 Engine?
The AMG M177 EVO engine produces the same 603 horsepower and 627 lb-ft of torque as in the 2026 Mercedes-Benz S-Class (S 63 E Performance) model, but full power comes on quicker, arriving at 5,500 rpm instead of 5,750 rpm, cutting the zero-to-60-mph time down one-tenth of a second to 3.6 seconds for the GLE. The revised GLS does it in 3.9 seconds. Both are capable of 174 mph at top speed.
Here’s a list of the mechanical changes to the flat-plane crank V8:
- New injection system with new intake and exhaust ports
- Revised intake camshaft
- Improved turbocharger housing
- New integrated starter generator in the mild-hybrid system that aids boost off the line
- New particulate filter to meet global emissions standards
The changes will likely only boost efficiency by 1 mpg, potentially bringing the AMG GLE and the larger AMG GLS to 18 mpg combined, up from the 17 mpg combined earned by the 2026 models. The EPA has not yet certified these 2027 models. The improvements might be neutralized by the 22-inch wheels offered on the GLE 63 S and the 23-inch wheel options on the GLS 63.
Additional Changes to the 2027 AMG GLE and GLS SUVs
Similar interior and exterior changes follow the lead of the 2027 Mercedes-Benz GLE introduced earlier this year, but with a rorty AMG spin.
The AMG Performance exhaust system enhances the twin-turbo V8 sound based on the selected drive mode, eliminating the need to manually select it through the touchscreen.
Both models have a new front end and an AMG grille with a chrome surround and vertical slats. Enlarged side air intakes and AMG-specific LED headlights further distinguish the AMGs from the core GLE and GLS models.
Both performance SUVs come standard with all-wheel drive (AWD) and an air-spring suspension with adaptive damping. A Trail mode raises the ride height by 2.2 inches for off-roading, but we expect the Sport or Sport+ mode, which lowers the ride height by 0.4 inches from its standard height at 75 mph, will be used more often. Active ride control with stabilizers on both axles counteract body lean and road imperfections to enhance the handling. An electronically locking rear differential further enhances grip and reduces slip on the inside rear wheel. This lets you go faster without the electronic brake checks of a simulated limited-slip differential.
For an SUV starting at nearly $135,000 last year (or more than $150,00 in the GLS’ case), Mercedes offers all its finest in the updated 2027, ranging from a Nappa-leather-covered steering wheel to a rainbow of leather upholstery colors, ranging from Red Pepper to Yacht Blue. Exterior colors range from Cirrus Silver Magno — that’s Magno, not like the fruit — to Ireland Mid Green Metallic.
Expect pricing to be announced nearer the on-sale date late this year.
