The verdict: Smooth, silent and strong, the Cadillac CT6 Plug-In hybrid drives well and looks sharp, but it suffers from an inferior interior.
Versus the competition: It’s a big step up from a Volt and outperforms rival German hybrid sedans that cost far more, but it falls short of those luxury rivals when it comes to interior appointments.
General Motors is making a big push for electrified vehicles over the next few years, and the technology won't be limited to mass-market Chevrolets. Exhibit one: the new 2017 CT6 Plug-In, a gas-electric hybrid luxury flagship sedan from the Cadillac brand. The last time Cadillac tried to do a plug-in hybrid, we got a gorgeous compact coupe built off the Chevy Volt platform — the horribly overpriced, short-lived Cadillac ELR. That formula did not work, so now Cadillac is trying something new.
The new car you see here is more unique than you might imagine: It's the only Cadillac you can buy in North America that isn't made here. The unique nature of this Cadillac means its biggest market isn't the United States — it's China, where the government is pushing electric vehicles hard in an effort to clean up stifling air pollution.
We're starting to see the same sentiment here, with California in particular pursuing zero-emission-vehicle requirements. But just because the next generation of cars is going greener doesn't mean people want to give up their creature comforts. So with fuel-efficient, green luxury in mind, Cadillac presents us with this leather-lined land yacht you can plug into a wall socket.
Stately to a Fault
The CT6 has been around a couple of years now, but you'd be forgiven for not knowing what it is; it isn't lighting the roads on fire with sales. In fact, Cadillac has sold just over 8,000 of them this year to date, making them an extremely rare sight on American roads.
That's not because the CT6 is unattractive: It's a long, low, sleek design that, frankly, doesn't look all that different from the smaller CTS sedan. Maybe it's the odd name. Maybe it's the fact that it doesn't look all that distinctive. Maybe it's because it doesn't look anything like the exquisite Cadillac Ciel or Elmiraj concept cars we saw prior to its launch, but folks aren't snapping this car up based on its looks.
Smooth and Silent
That's a shame, because the CT6 driving experience is quite good. The CT6 Plug-In operates a little differently from other models in the CT6 lineup, so a little technical background is necessary here.
The CT6 is the top Cadillac sedan, and it's available with four powertrains. The Plug-In combines a 2.0-liter, turbocharged four-cylinder engine with a special transmission — an electronically variable unit with two integrated electric motors. Sort of a mashup of a continuously variable automatic transmission and a planetary gearset, it's actually a bit more complicated than that. The transmission features four variable gear ratio spreads, three fixed ones and five clutches, but it feels similar to most CVTs I've driven. Total system output is 335 horsepower and 432 pounds-feet of torque — nothing to sniff at. It propels the car from zero to 60 mph in just 5.2 seconds, Cadillac says.
The hybrid system is powered by a lithium-ion battery pack that eats up about half of the CT6's previously available trunk space. It's an 18.4-kilowatt-hour pack — about as big as you'll find in a Chevrolet Volt — and has enough juice to propel the CT6 for about 31 miles on electric power alone. It recharges in a little over four hours on 240 volts and 20 amps, or overnight on a 120-volt household plug. That's a considerably better electric range than the CT6 Plug-In's rivals; the BMW 740e plug-in goes only 14 miles on a full charge, while the new 2018 Volvo S90 Hybrid manages only 21 miles.
Once the battery is empty, the gas engine provides power to the wheels and electricity to the system to keep you going more than 400 additional miles at an average of 26 mpg. (The 740e gets an estimated 27 mpg but goes only 326 gas-powered miles between fill-ups.) The gas engine can provide some direct supplemental grunt when you ask the CT6 to accelerate faster than the two electric motors alone can manage, but most of the time the CT6 stays in electric-only mode.
How It Drives
As a result, the CT6 Plug-In doesn't drive like a regular gas-powered Cadillac. Instead, it feels like a great big EV — silent, smooth and dead quiet, with the occasional gurgle, whine or thunk from the hybrid powertrain. Around town, it keeps things electric as much as possible — unless you dip your accelerator foot past the halfway point, in which case it fires up the gas engine after a slight hesitation. It's a weirdly unnerving feeling; just when you've called for more power, the car hiccups for a second before surging forward. The gas engine also fires up if you get above 78 mph on the highway, and there's a "hold" mode you can activate to use the gas engine all the time, reserving your battery power for low-speed city driving, where it's most efficient.
The same excellent steering, handling and ride quality we've experienced in other CT6s remain in the heavier plug-in hybrid, but the brakes take some getting used to. They're regenerative brakes, like you'll find in all hybrids and EVs, and the first bit of pedal travel engages the electric motors to slow you down before the brakes themselves start working, in order to recapture as much energy as possible into the batteries. Problem is, it feels artificial and nonlinear — like most hybrid car brakes.
The CT6 Plug-In allows you to adjust those regenerative brakes to be more or less aggressive. The standard setting is M4, which includes very little regeneration. You can use the paddles on the steering wheel or the console shifter to bump that up all the way to level M1, where you'll experience what's called "one-pedal driving." In this mode you rarely need to touch the brakes; as soon as you lift your foot from the go pedal the car aggressively begins to decelerate for maximum energy recapture. If you do a lot of city driving it'll take a little getting used to, but it can make a measurable difference in extending the car's electric range. I was able to coax 41 miles out of the CT6 in electric-only mode thanks to some careful, but not overly slow, driving.
Still Not There, Inside
The interior is big-car spacious, especially in back. Up front, you have a good view out over the long hood, and blind spot warning indicators help you out for the rear and side views. Interior materials are of mixed quality. Some of them, like the leather on the seats and doors, feel and smell wonderful (even if the "Cinnamon" color of this car's interior looks a bit too pumpkin-spice basic for my tastes).
Overall, though, this interior should be better; there are too many different materials on the dash and console, and not all of them feel up to snuff. The carbon fiber accents would be far better off in wood (when are automakers going to learn that carbon fiber is not a luxurious material?), and all the touch-sensitive controls do nothing to convey a feeling of solid, high-quality luxury. The all-digital gauges have a lot of information, but no artistry. Mercedes-Benz and Volvo do the best interiors these days, and this Cadillac flagship feels more premium than luxury. Apple CarPlay and Android Auto are standard, but Cadillac's own Cadillac User Experience system works perfectly well — sometimes even better than the glitchy Apple CarPlay I experienced.
There's tons of room in the backseat, which is where a lot of chauffeured overseas owners will be spending their time. There are video screens that pop up out of the front seatbacks, controls for the moonroof and privacy shade, and legroom aplenty. Much as I hate to say it, this would make an excellent premium Uber or Lyft vehicle — fuel-efficient for the owner to operate, comfy for passengers to ride in.
The all-digital gauges offer a lot of information but no artistry.
You won't be able to take those Uber passengers to the airport, however, as the trunk has only 10.6 cubic feet of cargo room, versus 15.3 cubic feet in the non-hybrid. It's seriously deficient versus the 14.8 cubic feet in the BMW 740e and the 13.5 cubic feet in the Volvo S90 Hybrid. If you want the most cargo room, though, splurge for the Porsche Panamera e-Hybrid, which is a hatchback that features 14.3 cubic feet behind the backseat and 44.0 cubic feet when you fold the rear seats down. You cannot fold the seats down in the Cadillac, BMW or Volvo.
Plenty of Standard Safety Equipment
Typical of large luxury cars, the 2017 Cadillac CT6 Hybrid has not been crash-tested by either the National Highway Traffic Safety Administration or the Insurance Institute for Highway Safety.
It comes with a significant complement of standard and optional advanced safety features. GM has been on its game in regard to producing such systems, and the CT6 Plug-In includes them all. Standard on the Plug-In are forward collision warning with front and rear autonomous emergency braking, pedestrian detection braking, a night vision camera, Cadillac's novel Rear Vision Camera Mirror, a 360-degree camera that can record what it sees while the vehicle is in motion, and more. The amount of safety gear Cadillac includes in the price of a CT6 Plug-In shames competitors that cost tens of thousands of dollars more and charge extra for such features.
Value in Its Class
Cadillac has placed the plug-in-hybrid variant of the CT6 in the high end of the trim list, slotting in between the Premium and the top, Platinum trim. A base CT6 with the turbocharged four-cylinder starts at $54,790 for 2017 (it jumps $300 for 2018), but the Plug-In checks in at $76,090. That's more than the starting price of a hot, twin-turbo V-6 Premium — an upcharge of $7,200, to be exact — but it does get you all the aforementioned standard safety equipment and on-board technology.
Even at that price, it undercuts most of its competitors, as well. The comparably sized BMW 740e starts at a whopping $90,095 and doesn't include many of the standard features the Cadillac does, nor does it go nearly as far on a full charge. That's thanks to a much smaller battery pack and heavier curb weight. Its interior is spacious and comfortable, but no more opulent than the Cadillac, reflecting a lack of luxurious materials common to BMW, as well.
Porsche offers a plug-in hybrid version of the slick new Panamera for 2018, but it's even more expensive — $100,650 to start, and like most Porsches it climbs very quickly from there. Perhaps the most intriguing alternative to the CT6 Plug-In is the new Volvo S90 Hybrid, which is also a plug-in. It's less expensive than the Cadillac, at $64,645 for a 2018 model, but doesn't have quite the spaciousness the BMW and Cadillac do. Compare all four here.
If you've decided to trade up from a smaller plug-in-hybrid to something in the luxury field, and you're still dedicated to the idea of driving something with an electrified powertrain, the CT6 Plug-In is a reasonable choice. It will satisfy in its driving dynamics, smoothness and silence, and will come across as nicer than any less-expensive hybrid on the market. It's a good step up from a Chevy Volt or Hyundai Sonata Plug-in Hybrid, and it's nicer inside than a Tesla Model S. You might also be the only person at your country club driving one.
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