Cadillac CT5 vs Lexus LS: Specs Compared

Also searched as Lexus LS vs Cadillac CT5 specs — both orientations show this same side-by-side comparison.

The Lexus LS is the more efficient of the two: it reaches 28 mpg combined versus 27 mpg for the Cadillac CT5, a 1 mpg advantage and costs about $100 less per year to fuel.

Across 4 measured categories, the Lexus LS leads in 4. Figures are EPA test data, not manufacturer claims.

2020–2026

Cadillac CT5

Midsize Cars · 52 configurations

27mpg combined (best)
All Cadillac CT5 specs

2015–2026

Lexus LS

Midsize Cars · 47 configurations

28mpg combined (best)
All Lexus LS specs

Head-to-head specifications

MetricCadillac CT5Lexus LS
Best combined MPG27 mpg28 mpg ✓
Best city MPG23 mpg25 mpg ✓
Best highway MPG33 mpg33 mpg
Lowest annual fuel costEPA estimate at 15,000 miles per year$2,800$2,700 ✓
Lowest CO2 output333 g/mi314 g/mi ✓
Engines offeredSIDISIDI & PFI, SIDI & PFI; Hybrid; with ADS, SIDI & PFI; Hybrid
TransmissionsAutomatic (S10), Manual 6-spdAutomatic (S10), Automatic (AV-S10), Automatic (S8)
DrivetrainsAll-Wheel Drive, Rear-Wheel DriveAll-Wheel Drive, Rear-Wheel Drive
Fuel typesPremiumPremium
EPA classMidsize CarsMidsize Cars
Years covered2020–20262015–2026
Configurations on record5247

Source: EPA fuel economy records via fueleconomy.gov. Best-case values across all recorded configurations for each model.

Cadillac CT5 vs Lexus LS dimensions and size

The Lexus LS is 12.6 inches longer than the Cadillac CT5 on a wheelbase 7.1 inches longer, and 1,139.8 lbs heavier. At over 200 inches, the larger of the two is past the comfortable limit of a standard 192-inch single garage bay once you allow walking room.

Cadillac CT5 versus Lexus LS exterior dimensions
DimensionCadillac CT5 (2026)Lexus LS (2026)Difference
Length193.7 in206.3 in12.6 in
Width (excl. mirrors)74 in74.8 in0.8 in
Height57.1 in57.5 in0.4 in
Wheelbase116.1 in123.2 in7.1 in
Curb weight3,799 lbs4,938 lbs1,140 lbs

Width excludes mirrors; add 8–12 inches for mirrors out. Figures are for the newest model year on record for each vehicle. See both drawn to scale.

Cadillac CT5 vs Lexus LS: what the numbers mean

Running cost over five years: at the EPA's 15,000-mile-a-year assumption the Lexus LS burns about $2,700 of fuel annually against $2,800 for the Cadillac CT5. That $100 yearly gap compounds to roughly $500 over five years and $800 over eight — often more than the price difference between two trims of the same vehicle, and the single largest running-cost line item separating these two.

City and highway economy: the Lexus LS leads in both cycles — 25 mpg city and 33 mpg highway against 23 and 33 mpg — so its fuel-efficiency advantage holds whether you commute in traffic or cover long highway miles.

Powertrain choice: the Cadillac CT5 is recorded with 1 distinct engine configuration (SIDI), the Lexus LS with 3 (SIDI & PFI, SIDI & PFI; Hybrid; with ADS, SIDI & PFI; Hybrid). Across 52 recorded Cadillac CT5 configurations and 47 for the Lexus LS, the wider the engine spread the more the real-world fuel efficiency depends on which version you actually buy, so check the specific model year and drivetrain rather than the headline number.

Drivetrain and class: the Cadillac CT5 is offered with All-Wheel Drive, Rear-Wheel Drive, the Lexus LS with All-Wheel Drive, Rear-Wheel Drive. All-wheel drive typically costs one to two mpg combined against the same vehicle in front- or rear-wheel drive, which is worth remembering when the gap between these two is small. The EPA classes them as Midsize Cars and Midsize Cars respectively — the class drives the interior volume, cargo space and passenger space each one is measured against.

Tailpipe emissions: at their cleanest configurations the Lexus LS emits 314 g/mile of CO2 versus 333 g/mile for the Cadillac CT5. Emissions track fuel consumption almost exactly, so the cleaner vehicle here is also the cheaper one to fuel.

CT5 vs LS: common questions

Which is better on gas, the Cadillac CT5 or the Lexus LS?

The Lexus LS is the more efficient of the two: it reaches 28 mpg combined versus 27 mpg for the Cadillac CT5, a 1 mpg advantage and costs about $100 less per year to fuel.

Which costs less to run per year?

By EPA estimates at 15,000 miles a year, the Lexus LS runs about $2,700 a year in fuel at its most efficient configuration, versus about $2,800 for the Cadillac CT5 — a difference of roughly $100 per year.

What engines do the CT5 and LS offer?

Cadillac CT5: SIDI. Lexus LS: SIDI & PFI, SIDI & PFI; Hybrid; with ADS, SIDI & PFI; Hybrid.

Are they in the same vehicle class?

Yes — the EPA classifies both the Cadillac CT5 and the Lexus LS as Midsize Cars, so they compete directly.

More CT5 comparisons

More LS comparisons

Comparison id: cadillac-ct5-vs-lexus-ls