They had to thin the sheet metal out in order to save the weight that they added back in with those HUGE mass dampers that are hanging off of the frame. Despite the advancements of new lightweight materials, they usually find a way to add that weight back in and then some.

 

Yep, I have the opportunity to interact with a wide variety of people in the "industry", from engineers at Chrysler to designers and reps from after-market companies.
Engineers are ALWAYS concerned about weight and emissions, but looking at the numbers thru the years, it appears that they can make it flimsier but not lighter. Typical "engineers"... LOL..