A Renault engine in your Benz C-Class? Absolutely not! Nobody would ever tolerate that sort of stuff. Except it’s already happened with front-wheel drive Mercs, so there’s no point in fighting it now.

The burden of Mercedes-Benz's considerable weight is on the C-Class's shoulders. After a few years of cutting corners to make more-populist cars, the automaker appears to be striving for a higher ...