At the end of last month reports surface that the W205 C63 also would not get a dual clutch transmission. This would make a lot of sense if the vehicle was all wheel drive as Mercedes would likely have the same torque concerns they do (and Audi as well) with sending a good amount of V8 twin turbo torque through a dual clutch transmission to all four wheels. We already know the engine is a 4.0 liter M177 V8 but the V8 twin turbo was confirmed with Tobias Moers on record. This motor also means the C55 name may be coming back since the motor will not be shared with the 63 AMG's.
So why no all wheel drive? The first reason is likely the weight. The CLS63 AMG and E63 AMG both perform very well with all wheel drive but they are about 130 pounds heavier than their rear wheel drive counterparts. That is a significant amount of weight especially with most of it coming over the front wheels and especially with the main rival from BMW (M3/M4) coming in at 3306 pounds.
With such a relatively low curb weight Mercedes would simply not be able to get close including all wheel drive, a twin turbo V8, and an automatic transmission. This despite the C-Class targeting weight savings of up to 220 pounds. Those 220 pounds though were not stated as to on what engine model, transmission, or driveline only as a maximum weight loss figure. Mercedes likely omitted specifying the weight savings in comparison to what previous model so that we would not be able to figure out the curb weight before they announced it. Not to mention they are still working on the C63.
It is a foregone conclusion that if the C63 had 4Matic it would not be as playful as a chassis as the M3 and would be prone to far more understeer. Mercedes seems intent on making the C63 more of a drivers car and will include the trick electronic differential from the SLS Black Series. That means the C63 should be more capable of competing with the M3 in balance and driving excitement.
Tobias Moers agrees stating, "You can have a lot of fun with the car on track with our 4Matic system, but I think the C-Class is more dedicated to fun-to-drive, more sporty, more race track--sometimes a little more sideways. That's the reason it's a rear-wheel drive car."
This also begs the question, if rear wheel drive why no dual clutch transmission? Perhaps the answer is Mercedes upping the torque significantly once the M3/M4 specs were released. This is the danger in BMW releasing their next generation numbers before Mercedes. Due to the turbo era however it is not the risk it used to be as BMW will simply offer a performance package option if they need to. Then Mercedes will likely fire back with their own. They both win as they both will make more money on the option which they are well aware of.
Additionally, it is important to note Tobias Moers did not state there never would be an all wheel drive C63. Will one come later as it did with the E63 refresh? Will they bump the power and do a C63 AMG S? Who knows, but the C63 just became a much more substantial rival for the M3. With approximately 130 less pounds to carry around than if it had the 4Matic system, it may just get close the CLA45 AMG's curb weight of 3600 pounds. It is practically a certainty it will be lighter than the W204 C63 AMG 3992 pounds. If Mercedes does lighten it by 220 pounds as they claim have been able to with the W205, that gives us 3772 pounds. We will have to wait and see.