Cadillac CT6: Which Version to Buy and Why
The Cadillac CT6 data supports three distinct buying directions. The first-generation 2.0 AT is the lightest and most economical choice, combining 269 hp with a kerb weight of 1,659 kg and combined consumption of 9.4 l/100 km. The first-generation 3.0 AT is the performance leader: 409 hp, 542 Nm and 0–100 km/h in 4.7 seconds.
The Cadillac CT6 data supports three distinct buying directions. The first-generation 2.0 AT is the lightest and most economical choice, combining 269 hp with a kerb weight of 1,659 kg and combined consumption of 9.4 l/100 km. The first-generation 3.0 AT is the performance leader: 409 hp, 542 Nm and 0–100 km/h in 4.7 seconds. Buyers wanting a non-turbo V-shaped 6-cylinder engine can choose between two first-generation 3.7 AT specifications or the restyled 3.7 AT. The second generation is listed from June 2023, but it has no recorded modifications, so its engine, performance, economy and weight cannot yet be compared.
Cadillac CT6 generations and versions
The first generation ran from April 2015 through June 2019 as a Sedan and contains four database entries: 2.0 AT, 3.0 AT, 3.7 AT with 340 hp, and 3.7 AT with 335 hp. The restyling began in April 2018 and remains part of this generation rather than a separate generation. It is also a Sedan and has one recorded version, 3.7 AT with 335 hp.
The second generation began in June 2023 and is a Sedan. It currently has no recorded versions. Consequently, a comparison involving searches for a Cadillac CT6 2025 or Cadillac CT6 2026 cannot be completed from this catalogue data: engine specifications, horsepower, transmission, drive, performance, fuel consumption, dimensions and weight are not measured.
Although the source lists three generation records because the restyling has its own record, they describe two numbered generations: the first generation, including its restyling, and the second generation.
Cadillac CT6 engine specs and horsepower
| Generation and version | Power | Torque | Displacement | Fuel | Cylinders and layout | Boost | Gearbox | Drive |
|---|---|---|---|---|---|---|---|---|
| First generation — 2.0 AT | 269 hp at 5,500 rpm | 400 Nm at 3,000–4,500 rpm | 1,998 cc | Gasoline, 95 | 4, Inline | Turbo | 8-speed Automatic | RWD |
| First generation — 3.0 AT | 409 hp at 5,700 rpm | 542 Nm at 2,500–5,100 rpm | 2,990 cc | Gasoline, 95 | 6, V-shaped | Turbo | 8-speed Automatic | AWD |
| First generation — 3.7 AT, 340 hp | 340 hp at 6,800 rpm | 385 Nm at 5,300 rpm | 3,649 cc | Gasoline, 95 | 6, V-shaped | No | 8-speed Automatic | AWD |
| First generation — 3.7 AT, 335 hp | 335 hp at 6,900 rpm | 386 Nm at 5,300 rpm | 3,649 cc | Gasoline, 95 | 6, V-shaped | No | 8-speed Automatic | AWD |
| First-generation restyling — 3.7 AT, 335 hp | 335 hp at 6,900 rpm | 386 Nm at 5,300 rpm | 3,649 cc | Gasoline, 95 | 6, V-shaped | No | 10-speed Automatic | AWD |
| Second generation | not measured | not measured | not measured | not measured | not measured | not measured | not measured | not measured |
All recorded engines use a Front, longitudinal installation and Direct injection (direct), with 4 valves per cylinder. The 2.0 AT has an 86 × 86 mm bore and stroke and a compression ratio of 9.5. The 3.0 AT uses 86 × 85.6 mm and a 9.8 compression ratio. Every 3.7 AT uses 95 × 85.8 mm and an 11.5 compression ratio.
Calculated from the recorded displacement and output, the 3.0 AT produces approximately 136.8 hp per litre. The 2.0 AT follows at approximately 134.6 hp per litre. The 3.7 AT with 340 hp delivers approximately 93.2 hp per litre, while each 335 hp 3.7 AT delivers approximately 91.8 hp per litre. On specific output, the two Turbo engines are therefore considerably ahead of the non-turbo alternatives.
Engine problems, reliability, oil requirements, air-filter specifications, engine-swap compatibility and replacement-engine availability are not measured in the supplied data. They cannot be used to recommend one CT6 version over another here.
Cadillac CT6 performance and fuel economy
| Generation and version | 0–100 km/h | Top speed | City | Highway | Combined |
|---|---|---|---|---|---|
| First generation — 2.0 AT | 5.9 s | 250 km/h | 10.7 l/100 km | 7.8 l/100 km | 9.4 l/100 km |
| First generation — 3.0 AT | 4.7 s | 250 km/h | 13.1 l/100 km | 9.0 l/100 km | 11.2 l/100 km |
| First generation — 3.7 AT, 340 hp | 5.9 s | 250 km/h | 13.1 l/100 km | 8.7 l/100 km | 11.2 l/100 km |
| First generation — 3.7 AT, 335 hp | 6.6 s | 240 km/h | 13.4 l/100 km | 7.5 l/100 km | 9.8 l/100 km |
| First-generation restyling — 3.7 AT, 335 hp | 6.6 s | 240 km/h | 13.4 l/100 km | 7.5 l/100 km | 9.8 l/100 km |
| Second generation | not measured | not measured | not measured | not measured | not measured |
The 3.0 AT reaches 100 km/h 1.2 seconds sooner than both the 2.0 AT and the 340 hp 3.7 AT, and 1.9 seconds sooner than either 335 hp 3.7 AT. Its 250 km/h maximum matches the 2.0 AT and 340 hp 3.7 AT, while exceeding the two 335 hp entries by 10 km/h.
That extra performance carries a consumption penalty against the 2.0 AT: the 3.0 AT uses 2.4 l/100 km more in the city, 1.2 l/100 km more on the highway and 1.8 l/100 km more combined. Curiously, the 340 hp 3.7 AT records exactly the same 11.2 l/100 km combined consumption as the 3.0 AT but takes 1.2 seconds longer to reach 100 km/h.
The 335 hp 3.7 AT is the highway-economy leader at 7.5 l/100 km, beating the 2.0 AT by 0.3 l/100 km. In the city, however, the 2.0 AT leads by 2.7 l/100 km. Its combined result is also 0.4 l/100 km lower.
Cadillac CT6 weight, clearance, tank and wheel sizes
| Generation and version | Kerb weight | Gross weight | Weight per hp | Ground clearance | Tank | Wheel sizes |
|---|---|---|---|---|---|---|
| First generation — 2.0 AT | 1,659 kg | not measured | 6.17 kg/hp | 155 mm | 72 L | 235/50 R18; 245/45 R19; 245/40 R20 |
| First generation — 3.0 AT | 1,853 kg | not measured | 4.53 kg/hp | 155 mm | 72 L | 235/50 R18; 245/45 R19; 245/40 R20 |
| First generation — 3.7 AT, 340 hp | 1,781 kg | not measured | 5.24 kg/hp | 155 mm | 72 L | 235/50 R18; 245/45 R19; 245/40 R20 |
| First generation — 3.7 AT, 335 hp | 1,834 kg | 2,390 kg | 5.47 kg/hp | 155 mm | 72 L | 235/50 R18; 245/45 R19; 245/40 R20 |
| First-generation restyling — 3.7 AT, 335 hp | 1,834 kg | 2,390 kg | 5.47 kg/hp | 140 mm | 73 L | not measured |
| Second generation | not measured | not measured | not measured | not measured | not measured | not measured |
The 2.0 AT is 122 kg lighter than the 340 hp 3.7 AT, 175 kg lighter than the 335 hp 3.7 AT and 194 kg lighter than the 3.0 AT. Nevertheless, the 3.0 AT has the best calculated power-to-weight result because its 409 hp yields 4.53 kg per horsepower. The 340 hp 3.7 AT ranks next at 5.24 kg/hp, followed by the 335 hp 3.7 AT at 5.47 kg/hp and the 2.0 AT at 6.17 kg/hp.
The restyled 3.7 AT retains the same 1,834 kg kerb weight and 2,390 kg gross weight as the matching earlier 335 hp version. Its tank grows by 1 L, but ground clearance falls by 15 mm. Overall vehicle length and other exterior dimensions are not measured in the data.
All measured CT6 versions use Independent, spring suspension at both ends, with Ventilated disc front brakes and Disc ventilated rear brakes.
Which Cadillac CT6 version should you buy?
Choose the first-generation 2.0 AT when consumption and lower kerb weight matter more than AWD. It is the only recorded RWD version, the lightest by at least 122 kg, and the combined-consumption leader at 9.4 l/100 km. It still records 269 hp, 400 Nm, 0–100 km/h in 5.9 seconds and a 250 km/h top speed.
Choose the first-generation 3.0 AT for maximum performance. Compared with the 340 hp 3.7 AT, it adds 69 hp and 157 Nm, improves 0–100 km/h by 1.2 seconds and keeps the same 250 km/h maximum. Both return 11.2 l/100 km combined, although the 3.0 AT uses 0.3 l/100 km more on the highway. It also has the strongest weight-per-horsepower figure.
Choose the first-generation 3.7 AT with 340 hp if you want AWD and a non-turbo V-shaped 6-cylinder engine without accepting the slower figures of the 335 hp specification. Relative to the 335 hp 3.7 AT, it has 5 hp more but 1 Nm less, is 53 kg lighter, reaches 100 km/h 0.7 seconds sooner and has a 10 km/h higher top speed. Its disadvantage is combined consumption: 11.2 versus 9.8 l/100 km.
Choose the first-generation 3.7 AT with 335 hp when highway economy matters within the non-turbo AWD group. Its 7.5 l/100 km highway and 9.8 l/100 km combined figures are better than those of the 340 hp version, but it is slower and heavier.
Choose the restyled 3.7 AT with 335 hp only if its recorded mechanical changes fit your priorities. Against the earlier matching 335 hp 3.7 AT, power, torque, acceleration, maximum speed, consumption, drive, kerb weight and gross weight are unchanged. The measurable differences are a 10-speed rather than 8-speed Automatic, a 73 L rather than 72 L tank, and 140 mm rather than 155 mm of ground clearance. Wheel sizes for the restyling are not measured.
Price, trim level and cars for sale are not included, so no claim can be made about what extra money buys or which version offers the best monetary value. On the available specifications alone, the 2.0 AT is the economy choice, the 3.0 AT is the performance choice, the 340 hp 3.7 AT is the quicker non-turbo AWD choice, and the 335 hp 3.7 AT is the more economical non-turbo AWD choice.