2016 Cadillac CT6 Body Structure

Cadillac will use an advanced mixed-material approach for the lightweight body structure of the upcoming CT6 range-topping sedan. The structure is aluminum intensive but includes 13 different materials. Sixty-four percent of the CT6 body structure is aluminum, including all exterior body.


Thirteen complex high-pressure die cast components make up the lower structure of the CT6 body, along with aluminum sheets and extrusions. The vehicle underbody uses steel close-out panels on the lower structure to create a bank vault-quiet cabin without the added weight of extensive sound-deadening material, often used to compensate for aluminum panels in the occupant compartment.

  • High-strength steel is used strategically to reinforce the body structure, and is also used in conjunction with high-strength aluminum to create a safety cage surrounding the occupants.
  • The structural portion of the B-pillar is constructed completely of high-strength steel, which was chosen to aid vehicle ingress, egress and visibility, in addition to mass savings and added cabin quietness.
  • A high-strength aluminum impact bar was added to the rear of the vehicle, and a combination of high-strength aluminum and steel was used for front and side impact zones to further increase passenger safety in the event of collisions.

A combination of aluminum spot welds, steel spot welds, flow drill screws, self-piercing rivets, laser welding, aluminum arc welding and hundreds of feet of structural adhesive are all used in assembling the body of the CT6.

  • 64% of the CT6 body structure is made with aluminum alloy
  • All exterior body panels are made with aluminum too
  • Almost all structural components in front of the firewall are aluminum (this is similar to the BMW E60 5-series)
  • Rear parcel is full aluminum


The photos below are of the body structure of the CT6  around the front fender reinforcement and the hinge pillar.  Notice the thickness of the hinge pillar (front to back of the vehicle) and the reinforcements from the wheel well into the fire wall?  These reinforcements will cause issues during a dash lift and dash roll.

PHEV Hybrid

General Motors is launching the 2017 Cadillac CT6 Plug-in Hybrid version of this vehicle with interesting battery location.  Learn more about it here.

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