Renault will supply a new 1.6 liter diesel to Mercedes while getting a 2.0 liter petrol/gasoline as well as access to more powerful V6 and V8 units.
(http://imgs.blackfalconmedia.com/2010/5/7/medium/1902794814490593561.jpg)
Mercedes-Benz and Renault swapping power plants (http://feeds.worldcarfans.com/~r/worldcarfans/Jxfz/~3/sbH2Yek5roY/mercedes-benz-and-renault-swapping-power-plants)