The 2017 Cadillac CT6 Plug-In will be a rare beast in the U.S.; fewer than 1,000 are likely to be sold each year.
In many ways, that’s a shame. This version of the CT6 large sedan is a worthy competitor among plug-in hybrid luxury cars, the rest of which will come from BMW, Mercedes-Benz, and Volvo.
Its rated electric range of 31 miles is roughly double that of the BMW 740e and Mercedes-Benz S550e, and its twin-motor hybrid transmission—similar to that of the Chevy Volt—is smoother than either of the Germans.
DON’T MISS: 2018 Cadillac CT6 – full review
We had a chance a couple of weeks ago to spend most of a day with a CT6 Plug-In, starting in New York City’s dense urban traffic and heading into the leafy green environs of posh Westchester County.
Like the Chevrolet Volt, the plug-in CT6 starts out operating solely on battery power up to 78 mph for its rated range, then switches over to become a conventional hybrid once the battery is depleted.
Unlike the Volt, however, full acceleration even with charge remaining in the battery will kick on the engine, like other plug-in hybrids whose electric motors aren’t quite sized to propel the entire weight of the car.
2017 Cadillac CT6 Plug-In specifications compared to those of competing plug-in hybrid large sedans
Also like the Volt, its performance is identical in both modes, with a quoted acceleration from 0 to 60 mph in 5.2 seconds.
The 18.4-kilowatt-hour lithium-ion battery in the CT6 has the same energy capacity as that of a Volt, and it too is liquid-cooled, but the pack is shaped very differently and sits just behind the rear seat at the front of the trunk.
The engine is a turbocharged 2.0-liter 4-cylinder, and between the engine and the two 90-kilowatt (120-horsepower) electric motors, total maximum power output is rated at 335 hp.
One advantage the CT6 has is light weight, due to the combination of high-strength steel and aluminum in the structure.
Cadillac says it’s roughly 1,000 pounds lighter than the BMW 740e, which also uses a 2.0-liter turbo-4 as its engine.
Both the Mercedes 550e and the upcoming Porsche Panamera 4 e-Hybrid use turbocharged V-6 engines to provide roughly equivalent performance.
From our drive notes, we took the following impressions:
- In either electric or hybrid operation, it was near impossible to tell when the engine was switching on; the suppression of noise and vibration is excellent
- Acceleration was mostly smooth, but in hybrid mode, we experienced a handful of very light judders that we don’t recall from our various times with a Volt in the same mode
- Like the regular CT6 we drove a few months earlier, the ride is firm and there’s a fair amount of tire noise for a luxury car
- We got 30 miles of electric range in either direction, showing that—like the Volt—the range ratings are achievable in real-world use when the weather’s temperate
- The regenerative brake paddle behind the left side of the steering wheel remains an excellent idea
- It’s extremely rare we suggest more chrome or other dressing-up of a design, but the rear view in particular of the CT6 Plug-In was plain, bordering on severe, for a car priced at $75,000
The CT6 comes in only a single trim level, which includes a sunroof, a rear-seat comfort package, and pretty much all of the available electronic active-safety systems you can get on a CT6.
Cadillac says that to get a comparable list of features in its competitors will run you from $98,500 (for the BMW 740e) to more than $115,000 for the Mercedes 550e or the Porsche Panamera 4 e-Hybrid.