Mercedes Swaps C63 PHEV for Inline-6 C53 Model

The automaker is retiring its turbocharged 4-cylinder in favor of a naturally-aspirated 6-cylinder engine.

Published on Feb. 6, 2026

Got story updates? Submit your updates here. ›

Mercedes-AMG has confirmed it will be replacing the current C63 sport sedan's turbocharged 4-cylinder plug-in hybrid powertrain with a new model featuring a naturally-aspirated inline-6 engine. The new C53 will borrow the 6-cylinder from the CLE53, though its power output is expected to exceed 500 horsepower. Mercedes cited difficulties meeting future emissions regulations as the key driver behind the switch away from the 4-cylinder.

Why it matters

The move away from the 4-cylinder PHEV C63 marks the end of an era for Mercedes' high-performance compact sedan. While the new inline-6 C53 is expected to deliver impressive power, the loss of the V8 option will disappoint some enthusiasts. However, Mercedes is committed to offering 6-cylinder and V8 powertrains in the future as it navigates tightening emissions regulations.

The details

Mercedes-AMG boss Michael Schiebe confirmed the powertrain change, saying the automaker will "stop offering the M139" 4-cylinder engine and replace it with the inline-6 from the CLE53 in the midsize segment. The new C53 will be a pure gas-powered model, without any hybrid assistance. While the CLE53's inline-6 produces 443 hp and 413 lb-ft, the C53 version is expected to exceed 500 hp.

  • Mercedes-AMG announced the powertrain change in February 2026.

The players

Mercedes-AMG

The high-performance division of Mercedes-Benz that develops and manufactures high-powered versions of Mercedes' production vehicles.

Michael Schiebe

The head of Mercedes-AMG who confirmed the powertrain change for the C63 model.

Got photos? Submit your photos here. ›

What they’re saying

“That means we will also have C53 in our portfolio. We're taking the combustion engine from the CLE53. No hybrid engine—pure inline-six-cylinder.”

— Michael Schiebe, Mercedes-AMG boss (Edmunds)

What’s next

Mercedes has not provided a timeline for when the new C53 model will debut, but it is expected to replace the current C63 PHEV in the coming years as the automaker transitions its high-performance compact sedan lineup.

The takeaway

Mercedes' decision to move away from the 4-cylinder PHEV powertrain in the C63 and instead offer a pure inline-6 model reflects the automaker's need to adapt to tightening emissions regulations. While enthusiasts may lament the loss of the V8 option, the new C53 is poised to deliver impressive performance as Mercedes remains committed to offering 6-cylinder and V8 powertrains in its future lineups.