When it comes to Japanese luxury cars, Lexus and Acura are the big guns. But Nissan’s Infiniti division has also been a pioneer in high end Asian imports, and builds some of the segment’s most interesting and enjoyable machines. Up until recently, however, there was no mid-weight V-8 sedan in their lineup, and that’s changed with this 2003 M45. While some say the M45 is a gap filler to please dealers, others say that it’s Infiniti’s best luxury-performance 4- door. Who’s right?

Perhaps both. The 2003 Infiniti M45’s pavement performance is as impressive as its subtle placement within a grand family tree. But does the youngest member of the family resemble its siblings or does the new kid stand alone?

Bearing a close mechanical resemblance to its “larger brother” the Infiniti Q45, these two cars are indeed cut from the same cloth. But the M45 looks more like a Lincoln-Mercury product than an Infiniti or Nissan, with a retro body that reminds us of a vintage Continental sedan. However, smoother, sculpted lines and the defined detail of its dynamic wedge shape running front to rear give the M45 a very contemporary update. A trim 110.2-inch wheelbase housing W-rated high performance 18-inch tires on chrome- drenched 8-spoke wheels furthers its up-to-date stance.

Anything but retro is the M45’s luxurious interior design. Trimmed in genuine bird’s eye maple with a smokey finish, the Q45-like dash features a performance-oriented four-dial instrument cluster, complete with amber lighting to accent the gauges. We have complained about the confusing nature of the Q45’s center stack controls for dual zone automatic climate and entertainment systems numerous times, and the M45 really doesn’t change our opinion. A 5.8-inch information display is standard, while DVD navigation and voice recognition are optional. Power adjustable front bucket seats wrapped in Infiniti’s own “Sojourner” leather invite both the driver and passenger to enjoy customized comfort. Optional climate controlled seats, which both heat and cool, also enhance the driving experience, while multiple front, side and head curtain airbags safeguard those on board.

With 3 inches less wheelbase than the Q45, the M45’s rear cabin took a beating on leg room. Still we found the fixed rear bench delivered sufficient comfort for three adults. The fully carpeted trunk with cargo mat measures out to be a decent 13.4 cubic feet of wide, low space.

But looks will only get you so far, so what else will sell someone this 3,800 pound gorilla? We’ll let the 4.5 liter double-overhead-cam V-8 speak for itself. M45 power ratings are 340 horsepower and 330 pound feet of torque, the same as the heavier Q45. So, this muscle- bound middle-weight is motivated to move.

The throttle response is immediate. The M45 hits 60 in an outstanding 6.3 seconds, and finishes the 1/4 mile in 15.0 seconds at 95 miles-per-hour. Linked to a 5-speed automatic transmission with manual shift mode, the drive train delivered strong power from idle to redline. But despite a great launch, the automatic’s manual mode didn’t provide the control we’d hoped for. It up shifts on its own at predesignated speeds. We’d like to be able to hold it in gear longer for maximum sprints. But even with that slight drawback, overall control isn’t something you have to fight for.

The M45 sports very responsive steering that promotes enthusiastic driving. The front strut/rear multi-link suspension, combined with the generous power, makes the M45 very nimble, often behaving like a car half its size. Yet ride quality is smooth and consistent as you would expect from a luxury sedan. And though our drivers did detect moderate body roll, the M45 stayed firmly planted and sure footed at all speeds.

When it’s time to stop, the M45 relies on its 4-wheel vented disc brakes. ABS with Brake Assist and Electronic Brake Force Distribution are standard. Pulling out some great numbers, they stopped this chariot from 60 in a fine average distance of 118 feet. A bit more ABS pulse than normal was detected, however, and there was some front wheel locking that subsided after a few runs. Overall stability proved solid, needing little correction. The EPA estimates fuel economy for the M45 at 17 city/23 highway. Our test loop average came in on the low side at 18 miles-per-gallon.

Nestled between the V-6 I35 and the flagship Q45, the Infiniti M45 carries a base price of $42,895. That’s 10-grand less than the Q45 and cheaper than competitive V-8 sedans from Lexus and Cadillac.

Strategically pricing the M45 well under the Q45, Infiniti has definitely closed the gap in their sedan lineup. But moreover, the M45 delivers the kind of total performance that is a pedigree of the Infiniti brand. So, regardless of its place on the totem pole, in the end the 2003 Infiniti M45 can hold its own quite nicely, and is more than worthy of its place at the starting gate!

Specifications

  • Engine: 4.5 Liter Dohc V-8
  • Horsepower: 340
  • Torque: 330 Lb Feet
  • 0-60 MPH: 6.3 Seconds
  • 1/4 Mile: 15.0 Seconds @ 95 MPH
  • 60-0 MPH: 118 Feet
  • EPA Mileage: 17 MPG City 23 MPG Highway
  • Motorweek's Mileage Loop: 18 MPG Mixed City/highway