Monday, April 13, 2015

2016 Cadillac CT6: A Closer Look At Its Innovative New Chassis

The 2016 Cadillac CT6 is a handsome new interpretation of Cadillac’s design language, but underneath the sculpted sheetmetal is what really makes Cadillac’s latest full-size offering special, which is intended to compete with the likes of BMW 7-Series and Audi A8.

Last week we were treated to a walk around of a 2016 CT6 cutaway display at the 2015 New York Auto Show, led by none other than Travis Hester, the lead CT6 engineer. Hester spared no detail as to what makes the 2016 CT6 a compelling alternative to German engineering.

What’s most intriguing is how the engineering team approached the design intent of the car. On paper, the car is aimed squarely at the full-size German sedans. But, in reality, Hester reveals the team benchmarked smaller cars like the Mercedes E-Class and Audi A6, while considering the driving characteristics of the brand’s own CTS. The idea behind this was to provide the large, luxurious feel of a full-size sedan, but to offer responsive and nimble driving dynamics.

Cadillac engineers weren’t dreaming, though. Rather than make do with the current GM parts bin, the new Omega platform emerges as a cutting-edge recipe of engineering. As such, Omega utilizes lightweight materials and advanced casting technology to provide the most dynamic driving experience ever seen on a full-size sedan.

An example of the aforementioned advanced casting can be seen in a ribbed aluminum casting, which begins at the shock tower and runs to the rear of the CT6. Hester explains normally this structural component would take some 35 pieces to assemble, but with the new casting technology, it’s one single piece. He also noted that there are no less than 13 high-pressure die-cast aluminum pieces in the structure of the CT6. Including the transmission tunnel.

These futuristic components lead to increased structural rigidity at critical stress points for the car. It also allows for unnecessary weight to stay off the car, embracing the goal of the engineering team further.

While aluminum is also used extensively with the Omega platform, it isn’t the sole material used in the 2016 CT6, and there are some drawbacks. For example, its density makes for a downright terrible sound buffer from the outside. Because of this, a lot of sound insulation would have been required to achieve the goal of “bank vault” quietness in the cabin of the CT6. Sound insulation, of course, is dead weight. Hester doesn’t like dead weight.

As a solution, Hester and the rest of the CT6 team implemented high-strength steel in strategic points around the body that surrounds the cabin. In doing so, far less sound insulation (read: weight) was needed. Proving that sometimes, the heavier metal can still contribute to the lightest solution possible.

The mixed material usage, which also includes doses of magnesium, is something we expect to see more of from General Motors to combat rising fuel economy standards. Piecing all of these metals together are flow-drilled screwed rivets, traditional welding and aluminum spot welding in strategic locations, along with a total of 118 meters of fighter-jet-like structural adhesives. The adhesives, along with special steel coating, prevents corrosion between the different elements making up the structure.

The biggest news surrounding the 2016 Cadillac CT6 is the incredibly low curb-weight, which undercuts competitors by 600 pounds. And as we all know, a base CT6 is said to weigh less than the smaller Cadillac CTS. Something achieved through the right mix of materials as detailed above.