Like previous generations, the WK2 Grand Cherokee chassis is a steel unibody. Unlike previous generations, it features four-wheel independent suspension for better on-road handling. The WK2 and 2011 Durango use a Chrysler designed and engineered platform/chassis that Mercedes-Benz later used for the Mercedes-Benz W166 series. The Chrysler designed platform was part of the DaimerChrysler engineering projects that were to launch the WK2 Grand Cherokee with the Mercedes-Benz ML to follow. However, due to the subsequent sale and bankruptcy of Chrysler, the Grand Cherokee launch was delayed and the ML launched before the Grand Cherokee.
In 2006, development began on the next-generation M-Class and spanned over a period of 5 years, a much shorter duration than its predecessor. In 2008, the final design by Emiel Burki was approved and patented domestically on 16 December 2008 (U.S. design patent filed on 15 June 2009). The newly redesigned M-class (chassis name W166) was introduced in pre-production form 10 June 2011 as a 2012 model. The first customer-designated W166 rolled off the Vance production line on 20 July.
