The base CT6 comes standard with a 2.0-liter four-cylinder turbo engine (265 hp, 295 lb-ft) and includes 18-inch wheels (19s with the V6), front and rear parking sensors, LED headlights and taillights, heated mirrors, a power tilt-and-telescoping steering wheel, an auto-dimming rearview mirror, leather upholstery, eight-way power front seats (with two-way power lumbar), driver-seat memory settings and dual-zone automatic climate control. Also standard on the technology front are GM's OnStar system (with 4G LTE connectivity and Wi-Fi hotspot capability), Bluetooth, a 10.2-inch touchscreen with Cadillac's CUE interface, Apple CarPlay and Android Auto smartphone integration, a rearview camera, voice controls, four USB charge ports, wireless charging and an eight-speaker Bose sound system with satellite radio and three audio USB ports. An optional Driver Awareness and Convenience package adds a panoramic sunroof, automatic high-beam headlights, automatic wipers, power-folding mirrors, heated front seats, a navigation system and an array of extra safety features (see Safety section for details). There's also an optional V6 engine rated at 335 hp and 284 lb-ft. The Luxury trim starts with all of the above equipment and adds another engine choice, a 3.0-liter twin-turbo V6 (404 hp, 400 lb-ft), automatic parking system, auto brake hold (prevents forward/rearward creep when your foot is off the brake), a hands-free trunklid, four-way power lumbar for the front seats, front passenger-seat memory settings, a top-down 360-degree parking camera system, rear side window shades, upgraded interior lighting and a 10-speaker Bose surround-sound audio system. The optional Comfort package adds ventilated front seats and heated rear seats. Moving up to the Premium Luxury gets you an upgraded gauge cluster display, a head-up display, and the Enhanced Vision and Comfort package as standard.