There’s a special corner of automotive history reserved for cars that showed up early, tried something bold, and then vanished before the market fully caught on. The first-generation Infiniti M45 lives squarely in that space. Built for just two model years, the 2003–2004 M45 was Infiniti’s attempt to fuse old-school V8 muscle with luxury sedan sensibilities.
It arrived before sports sedans became mainstream, before every automaker discovered launch control, and before “performance luxury” became a marketing checkbox. And because of that timing, it slipped into obscurity. Today, that same timing makes it fascinating. You get a naturally aspirated V8, rear-wheel drive, genuine Japanese build quality, and a design that still feels purposeful. Best of all, you can still buy one for less than used-Camry money.
A 340-Horsepower Luxury Sleeper That Arrived Before Its Time
Too Early To Be Appreciated, And Too Rare To Be Recognized
Under the hood of every first-gen M45 sits a 4.5-liter naturally aspirated V8 producing 340 horsepower and 333 pound-feet of torque. Power comes from Nissan’s VK45DE engine, routed through a five-speed automatic transmission to the rear wheels. That was serious output in 2003. The M45 could sprint from 0–60 mph in 6.3 seconds, which put it firmly in BMW 540i territory at the time, and ahead of plenty of luxury sedans that leaned harder on comfort than speed.
A V8 Sedan With Real Attitude
But numbers only tell part of the story. This car delivers its power the old-fashioned way: linear throttle response, a deep V8 growl, and no turbo lag to negotiate. It feels muscular without being crude, and refined without losing its edge. Suspension tuning leans sporty, with a firm ride that communicates the road. Steering is hydraulic and full of feedback. You don’t drive this car with your fingertips. You drive it with intent. And here’s the kicker: Infiniti sold only about 8,000 examples in the U.S. across both model years. That makes it rarer than many enthusiast icons people won’t stop talking about.
Why The First-Gen M45 Was Different From Every Other Luxury Sedan
The M45 wasn’t chasing European luxury sedans. Infiniti went its own way. Instead of building a soft executive cruiser, Infiniti based the M45 on the Japanese-market Nissan Gloria platform and gave it aggressive styling, bolstered seats, and a performance-first attitude.
You also get a surprisingly roomy interior, a large trunk, and standard features that were impressive for the era: xenon headlights, heated leather seats, dual-zone climate control, Bose audio, and stability control. This was not a stripped-down performance experiment. It was a fully realized luxury sedan with a big V8. In hindsight, it feels like Infiniti was testing the waters for cars like the later M56 and Q70.
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Used Prices Make This One Of The Best V8 Sedan Bargains Around
Infiniti M45 Used Prices: How Much Does This Sleeper Cost Today?
Despite its performance credentials and rarity, most first-gen M45s trade between $5,000 and $10,000, depending on mileage and condition. Exceptional low-mileage examples can push higher, but even clean drivers remain remarkably affordable. That puts it in the same price bracket as high-mileage economy sedans, yet you’re getting a V8 luxury car that once stickered at $42,300.
Part of the reason prices remain low is simple: most people forgot this car existed. It doesn’t carry the collector halo of German rivals, and it doesn’t have the tuner fame of certain Japanese models. That anonymity is exactly what keeps it accessible. For car nerds willing to dig a little deeper, it’s a gift.
Rarity, Attrition, And Why Clean Examples Are Getting Harder To Find
With only around 8,000 sold originally, attrition matters. Many M45s have been driven hard, neglected, or simply used up over two decades. Because of this, finding a clean, stock example with service records is becoming more challenging every year. And unlike mass-market sedans, there isn’t a huge supply waiting in the wings. This is how sleeper classics begin their slow climb.
It’s not dramatic. It doesn’t happen overnight. But once enthusiasts realize how rare these cars are, and how much performance they offer per dollar, demand starts to creep upward. We’ve seen this story many times before with models that went unnoticed when launched, but hid key character traits that appealed to enthusiasts’ changing desires over time.
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Old-School Japanese Luxury With Real Staying Power
The Definition Of A Diamond In The Rough
Step inside a first-gen M45, and you’re greeted by thick leather, brushed metal accents, and a layout that favors drivers who actually like driving. The seats are supportive without being punishing. The dash is straightforward. Controls make sense. There’s no giant touchscreen dominating your field of vision. Instead, you get physical buttons, clear gauges, and a cockpit that feels built around the person behind the wheel. It’s a refreshing contrast to modern luxury interiors that sometimes prioritize aesthetics over usability.
Cargo space is generous, the rear-seat room is respectable, and visibility is better than many newer sedans with high beltlines and tiny windows. This is a car you can road-trip comfortably or commute in daily, assuming you’re okay with feeding a V8.
Reliability, Ownership Reality, And Why This Sedan Deserves Respect
The VK45DE V8 has proven to be a durable engine when properly maintained. Regular oil changes, cooling system care, and attention to suspension wear go a long way. These cars aren’t maintenance-free, but they’re far from fragile. Parts availability remains solid thanks to shared Nissan components, and independent shops are generally familiar with the platform.
Fuel economy hovers around 16 mpg city and 22 highway, which won’t thrill your wallet, but nobody buys a naturally aspirated V8 sedan expecting hybrid efficiency. What you do get is a driving experience that feels increasingly rare. And that’s what makes the M45 special.
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TopSpeed’s Take: The M45 Is A Unicorn
If You Can Find One, It’s Worth Consideration
The first-generation Infiniti M45 didn’t get its moment in the spotlight. It arrived too early and disappeared too quickly. But time has a way of reshuffling the deck. Today, the M45 stands out as a rare example of Japanese luxury done with muscle-car power. It offers real performance, genuine comfort, and a level of anonymity that makes it one of the best sleepers you can still buy. If you’re looking for something different, something powerful, and something that won’t show up at every stoplight, this forgotten V8 sedan deserves a place on your shortlist.