2003 Infiniti M45 Road Test Specs | Edmunds

2003 INFINITI M45 - Road Test Specs

2003 Infiniti M45 Sedan

(4.5L V8 5-speed Automatic)


Model year2003
Style4dr Sedan (4.5L 8cyl 5A)
Base MSRP$42,300.00
As-tested MSRP$50,055


Drive typeRWD
Engine typeV8
Displacement (cc/cu-in)4.5
Horsepower (hp @ rpm)340 @ 6400
Torque (lb-ft @ rpm)333 @ 4000
Transmission type5-speed shiftable automatic


Suspension, frontIndependent strut, stabilizer bar, coil springs
Suspension, rearmulti-link
Steering typeSpeed-sensitive rack-and-pinion
Tire brandBridgestone
Tire modelTuranza
Tire size, frontP235/45R18
Tire size, rearP235/45R18
Brakes, frontFront ventilated disc/rear ventilated disc

Track Test Results

0-45 mph (sec.)4.2
0-60 mph (sec.)6.4
0-75 mph (sec.)9.4
1/4-mile (sec. @ mph)14.8 @ 95.5
Braking, 30-0 mph (ft.)30.1
60-0 mph (ft.)117.8
Slalom, 6 x 100 ft. (mph)59.5
Skid pad, 200-ft. diameter (lateral g)40
Sound level @ idle (dB)Below 50
@ Full throttle (dB)69
@ 70 mph cruise (dB)71

Test Driver Ratings & Comments

Acceleration commentsLike most modern Nissan/Infiniti drivetrains, this one is a sweetheart. Plenty of torque from idle to redline (which occurs at 6,700 rpm) and even a slight high-rpm rush above 5,000 rpm. Upshifts were quick and crisp, occurring consistently at 6,500 rpm. The only real disappointment was an inability to manually control the upshifts, this despite a manual-shift mode and separate shift gate for the automatic. At full throttle, the M45 basically upshifted at the same points (6,500 rpm again), regardless of transmission mode (seems kind of uppity for a modern-day muscle car, even a "muscle car with brains" as Infiniti likes to describe it). Still, the torque and refinement of this drivetrain is hard to deny, even if it thinks it's smarter than the driver.
Braking ratingGood
Braking commentsThe M45's ABS made noise on par with most modern vehicles, but pedal vibration was well damped and quite subtle. The pedal's feel when invoking maximum braking could have been more progressive — it felt a bit "squishy" near the bottom of its travel. The actual braking numbers were impressive for such a heavy vehicle, and the distances went up only five feet over the course of three emergency stops, so fade was minimal. The car remained straight and suffered only slight front-end dive during each stop.
Handling ratingAverage
Handling commentsThe M45 is simply a big, heavy car...which made its ability to rotate in the slalom somewhat bizarre. Careful use of the throttle allowed me to bring the rear end around while exiting the final cones, but careful is the key word here. The sedan never actually spun out of control on me, but the potential was certianly lurking out there (sort of like with Infiniti's other sedan, the G35). Steering feel isn't on par with (or even close to) the 5 Series, but there's no dead spot and the thick wheel was easy to control during rapid left-right transitions. An overall lack of body roll was impressive considering the car's size and weight. — Karl Brauer

Testing Conditions

Elevation (ft.)85
Temperature (°F)78
Wind (mph, direction)10-12

Fuel Consumption

EPA fuel economy (mpg)Auto 17/23 Manual /
Edmunds observed (mpg)16
Fuel tank capacity (U.S. gal.)21.1

Dimensions & Capacities

Curb weight, mfr. claim (lbs.)3851
Length (in.)197.2
Width (in.)69.7
Height (in.)57.6
Wheelbase (in.)110.2
Legroom, front (in.)42.1
Legroom, rear (in.)32.5
Headroom, front (in.)39.8
Headroom, rear (in.)37.3
Seating capacity5
Cargo volume (cu-ft)13.4
Max. cargo volume, seats folded (cu-ft)13


Bumper-to-bumper4 years / 60,000 miles
Powertrain6 years / 70,000 miles
Corrosion7 years / miles
Roadside assistance4 years / 60,000 miles
Free scheduled maintenance3


Front airbagsStandard
Side airbagsStandard
Head airbagsStandard
Antilock brakesStandard
Electronic brake enhancementsElectronic Brake Distribution
Traction controlStandard
Stability controlStandard
NHTSA crash test, driverNot tested
NHTSA crash test, passengerNot tested
NHTSA crash test, side frontNot tested
NHTSA crash test, side rearNot tested
NHTSA rollover resistanceNot tested

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