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You'll Like The 2008 INFINITI M45 If...

If you’re in the market for a sport sedan with plenty of room, spirited performance and loads of comfort and convenience touches, any member of the Infiniti M lineup is worth a test drive. Those with distinct enthusiast leanings should find the V8-powered M45 with a Sport Package particularly attractive.

You May Not Like The 2008 INFINITI M45 If...

Even in this latest incarnation, the Infiniti M’s styling cues remain somewhat understated, perhaps too much so for buyers with more flamboyant tastes. If you’re one of the vanishing breed who still believes that any proper sport sedan simply must have a manual transmission, an M35 or M45 in any guise just won’t fill your bill.

What's New

The Infiniti M enjoys an exterior facelift and multiple lesser interior enhancements while gaining a new, all-wheel drive M45x variant. The 2008 lineup also sees Lane Departure Prevention technology added to the existing Lane Departure Warning system and M Sport models replaced by an available Sport Package for rear-drive versions of both M35 and M45.

Interior Features

The spacious Infiniti M cabin has a contemporary classic flavor highlighted by supple leather upholstery with African rosewood or textured-aluminum accents. Restyled main gauges reflect the latest Infiniti white-and-purple lighting motif for even greater legibility, and supplemental functions can be accessed by logically arrayed switchgear on the instrument panel’s center stack — or by a user-friendly controller that displays information on a 7.0-inch color LCD screen. Both front seats feature 10-way power adjustability, the fixed-back, contoured rear bench provides generous head and legroom for adults in the two outboard spots while a pull-down center armrest conceals a modest pass-though opening to the M’s 14.9 cubic-foot trunk.

Exterior Features

A subtle but wide-ranging exterior revamp adds a bit bolder character to the 2008 M lineup. Its crisply rendered nose gains an edgier grille, new fog lamps and reshaped lower air inlets. Out back, an even more comprehensive makeover brings redrawn fenders and a higher-profile decklid plus more elegantly shaped and better-integrated taillamps that complement an even-tidier fascia. Both M35 and M45 models come with 18-inch aluminum wheels mounted with V-rated 245/45 all-season tires, but stepping up to the Sport Package upgrades that to 245/40R19 high-performance tires on unique alloy rims and includes more aggressive front and rear soft-trim contours, integrated side sills and charcoal-colored headlamp bezels.

Driving Impressions

Although the specific driving characteristics of each model vary by engine and powertrain configuration, all variations on the M theme come standard with a genuinely engaging personality and offer an impressive combination of comfort and control that should please a wide range of potential buyers. Based on the latest version of Nissan’s lauded FM (Front Mid-ship) platform, also used in the 350Z and Infiniti G35 and G37, the M matches its nicely-sorted fully-independent suspension with well-weighted and quick-responding power steering. Those commendable dynamic qualities get ratcheted up a tangible notch on rear-drive models fitted with the optional Sport Package. Although the heavier all-wheel-drive M35x and M45x models sacrifice a bit of enthusiast appeal, Nissan’s outstanding AWD system can seamlessly transfer torque from front-to-rear and side-to-side as changing traction conditions warrant, making it a feature well worth considering for those who live outside of the Sun Belt.

Pricing Notes

The Manufacturer’s Suggested Retail Price for an M35 starts at just over $44,000, with an M35x at closer to $46,000. The V8-powered M45 is around $50,000 and the M45x is about $54,000. However, when you add the admittedly comprehensive Premium Package and polished wheels to the top-of-the-line M45x, that figure will approach the $65,000 mark. Regardless of model, the entire Infiniti M family tends to hold a tangible price advantage over comparably equipped key competitors from Audi, BMW, Lexus and Mercedes-Benz. That edge should continue in the long run as well, where the residual values are projected to equal or top those of the prime rivals. And, expect an M45 to fare slightly better than an M35 over time.

Notable Equipment

Both the M35 and M45 have all of the luxury appointments you’d expect in a premium sedan-and more. Complementing leather and wood and aluminum trim are a bounty of power assists plus dual-zone climate control, 160-watt AM/FM/CD/MP3 audio with six-disc changer, Intelligent Key remote locking and ignition, one-touch power moonroof and a power tilt and telescoping steering column capped by a four-spoke wheel with switches to operate the audio, cruise control, phone and vehicle information functions. All versions come with Vehicle Dynamic Control (VDC), anti-lock brakes (ABS), Brake Assist (BA), Electronic Brake force Distribution (EBD), corner-following bi-xenon adaptive headlamps (optional on the M35x) and front, front-side and side-curtain airbags.

Notable Options

Tiered option groups allow personalization of any M model with the best of everything available from Infiniti. The three key packages, in ascending order, are Technology, Advanced Technology and Premium. Included in those packages are voice-recognition DVD-based navigation, a RearView backup monitor, Intelligent Cruise Control, Preview Braking, Lane Departure Warning, Lane Departure Prevention, two levels of Bose premium audio systems, a 9.3-gigabyte Music Box hard drive, single or dual-screen rear-seat DVD video systems, heated and power-reclining rear seats and rear air conditioning. Enthusiasts can opt for the Sport Package, which includes a tauter suspension with Rear Active Steer, plus 19-inch wheels and tires, sport seats and unique body trim.

Favorite Features

Bi-xenon Adaptive Front lighting System (AFS)Optional on the M35x but standard on all other M models, these high-intensity headlamps are linked to the steering system and can angle their brilliant blue-white beams into a corner to provide an even better look at what lies ahead. Optional Rear Active Steer (RAS)Included in the Sport Package, Rear Active Steer varies the geometry of the rear wheels in response to both road speed and driver steering inputs to deliver even more immediate and positive reactions during spirited cornering.

Under the Hood

Smooth and sophisticated, the M35’s 3.5-liter V6 and the M45’s 4.5-liter V8 are enthusiastic, albeit somewhat thirsty, powerplants. Made of lightweight aluminum and featuring variable valve timing to maximize operating efficiency, both are backed by a responsive five-speed automatic transmission with intuitive electronic controls that adapt to a driver’s individual style, plus a neat throttle-blipping feature that matches engine rpm to vehicle speed for even smoother downshifts. With 275 horsepower and 268 pound-feet of torque, the V6 propels an M35 from zero to 60 miles per hour in just over six seconds – or slightly more for the heavier all-wheel-drive M35x. Rated at 325 horsepower and 336 pound-feet of torque, the larger V8 in the M45 drops that interval into the mid-to-high five-second range. 3.5-liter V6275 horsepower @ 6200 rpm268 lb.-ft. of torque @ 4800 rpmEPA city/highway fuel economy: 16/23 (RWD), 16/22 (AWD)4.5-liter V8325 horsepower @ 6400 rpm336 lb.-ft. of torque @ 4000 rpmEPA city/highway fuel economy: 16/21 (RWD), 14/20 (AWD)

Editors' Notes

The Infiniti M sedan line distinctively blends sport, luxury and performance characteristics with V6 or V8 power. For 2008, a comprehensive restyle, multiple interior tweaks and new tech features give this premium sedan family even greater market appeal. And, for the first time, there’s a choice of rear-drive (M35 or M45) or all-wheel-drive (M35x or M45x), and the availability of Lane Departure Prevention (LDP). Rated by the EPA as a full-size sedan, with interior space that nearly matches an Audi A8, BMW 7 Series and Mercedes S-Class, the Infiniti M is priced closer to the smaller Audi A6, BMW 5 Series and Mercedes-Benz E-Class counterparts — along with key Japanese mid-size rivals like the Acura RL and Lexus GS. The Infiniti M’s high-value and high-content formula is further reinforced by excellent reliability and strong customer satisfaction ratings.

Road Test Video Reviews

2008 INFINITI M45 Owner Reviews

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My M45X boasts luxury and reliability while being safe and speedy!

2008 INFINITI M45 4dr Sdn AWD

The best luxury vehicle with a powerful V8 engine I've owned. There are all sorts of available features like lane departure technology for safety. I absolutely love the AWD, especially for snowy winters. The interior is plush leather with beautiful wood. The ride is speedy, with quick acceleration but ever so smooth. My vehicle also has added features for enjoyment like the TV/DVD player, seat warmers/coolers, back window sunshade, etc. I have had no mechanical issues nor fixes since owning this car. The only thing I noticed is I do have to add extra oil every now and again, but the car is over 10 years old with a V8 engine. I would buy this car again.

- Rachel H

My vehicle has leather seats, a sunroof.

2008 INFINITI M45 Base

I love my car, it's great. Beautiful leather seats, and they go back. Also the front seats have rear warmers. The only true complication is that gas is extremely expensive. But that's what I should expect for this type of vehicle. Totally recommended.

- Jessica S

Tons of trunk space and leg room. Lots of storage space, and very good on trips.


Air conditioner doesn't work and has not worked since purchasing, brakes squeal, and water comes in my window after rain. I love the built in GPS and DVD player.

- Tanya S

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