2010 Mercedes-Benz S400 Hybrid Car Reviews

First, however, we must discuss the novelty of an S-class hybrid.
Hybrid power

Unlike the Lexus LS 600h, in which Lexus merely chose to add a big hybrid drive system to the LS' existing V-8, giving it tremendous power, Mercedes-Benz downsized the S-class engine, replacing the base level 5.5-liter V-8 with an Atkinson cycle 3.5-liter V-6.

A 20-horsepower electric motor assists that engine.