The battle of the full-size luxury sedans became all the more competitive through the 1980s, as Japanese brands like Nissan and Toyota turned their attention to getting thebetter of the trend-setting Germans. Having already largely conquered the compact market through the middle of the decade, the Japanese automotive industry wanted to show that it could nail a car designed to make you feel special, as opposed to one that’ll simply get you to your destination.
Nissan elected to go the extra mile in its attempts to tempt buyers into spending money on its latest creation.
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1990 Infiniti Q45 Black Front 3/4 Angled ViewInfiniti
For a long time, the likes of BMW, Cadillac, and Mercedes-Benz had enjoyed the full-size luxury sedan market all to themselves, but the end of the 1980s signaled a considerable sea change. The Japanese were coming, and theymeant business.
The big manufacturers, namely Honda, Nissan, and Toyota, were aware that their names were more closely aligned with saving money than luxury, so each founded its own luxury-focused spin-off brand. Honda had Acura, Toyota developed Lexus, and Nissan established Infiniti. Acura’s Legend was the first such model to reach the market in 1986, before Lexus’ LS and Infiniti’s Q45 were unleashed in 1989.
Like most range-topping luxury sedans of the time, the Q45 came loaded with a large, naturally aspirated V8 under the hood. With a displacement of 4.5-liters, the posh Nissan was able to send 278 horsepower and 292 lb-ft of torque to the rear wheels. In order to ensure as smooth a drive as possible, the car used a four-speed automatic transmission. For most models, an independent suspension setup was included, which was tuned to provide a compliant and comfortable ride.
Infiniti Priced The Q45 Above Lexus – And Paid For It In The Showroom
Knowing they had little to no brand awareness from the outset, the Japanese method of breaking into the luxury market was to seriously undercut the likes of Mercedes. Whereas a 4.2-liter V8-powered 420 SEL would have set you back a cool $62,500 in 1990, and a 7-Series was just shy of $50k, a Lexus LS 400 demanded just $35,000.
Considering Lexus poured around $1 billion into the car’s development, this was a bit of a bargain. Infiniti believed it had built a better product than its rival, however, and instead asked $38,000 if you wanted a Q45 to grace your driveway.
In Infiniti’s defense, the Q45 was considerably more powerful than its Lexus rival, as the LS 400’s 4.0-liter V8 only brought 250 hp and 268 lb-ft of torque to the battle. Still, power isn’t everything, and the fact that Toyota started from a blank sheet with the LS 400 showed. It felt more special as a result, and when twinned with its cheaper MSRP and the fact that it had achieved better brand awareness at the time, it therefore fared much better in the sales race than the Q45. Whereas Infiniti managed to shift just under 14,000 Q45s in 1990, Lexus waved off over 63,000 examples of its LS 400.
The Hydraulic Active Suspension That Made The Q45a Unlike Any Other Luxury Sedan
1989 Infiniti Q45 Selection PackageInfiniti
While the Q45 got badly beaten by its Lexus rival in the luxury sedan sales race, it deserves to be remembered for more than that. One of the best ways of achieving an excellent ride is by using active suspension, which can get softer or stiffer depending on the kind of road or driving the vehicle is undertaking. The advantage of this is that the car can provide its occupants with a supple ride when cruising along, before stiffening itself up when tackling a fun driving road to help reduce body roll. Such a setup can also prevent a car from pitching from the front and rear under acceleration and braking, further improving the ride quality.
Like its LS 400 rival, the Q45 was made available with such a system. Unlike the Lexus, though, which used a more common airbag-based setup, the Q45 used one that relied on hydraulic actuators. Essentially, an actuator that used hydraulic fluid to function was installed on each corner of the car, and could be filled or emptied depending on which corner of the car needed leveling the most.
To work this out, a series of G sensors fed information about the car’s position to the onboard computer, which would then send the right amount of fluid to each actuator to keep the car level.
The system could also raise the car by 0.78 inches on command, which was useful for clearing things like speed humps on the road. Every specimen equipped with it was designated the Q45a by Infiniti.
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White 1994 Infiniti Q45a back endBring a Trailer
The main benefit of the hydraulic system over the air suspension setup used by rivals like the LS 400 was that, because hydraulic fluid is denser than air, the system ensured the car remained even stiffer than that using air. This meant the car’s tires could make better use of available grip. In addition, the hydraulic system is slightly more responsive than an air setup, meaning any pitch and roll can be corrected faster, which helps boost the handling characteristics even further.
Having made its debut for the 1991 model year, it ended up lasting just five years before it was ditched in 1996. As it turned out, there were several key drawbacks that meant it ultimately lost out to air suspension in the technology race.
Infiniti’s System Was Heavier And More Expensive
White 1994 Infiniti Q45a sideBring a Trailer
Firstly, while the system provided superior handling to an air setup, the ride quality wasn’t quite as good. Seeing as the main point behind a luxury sedan is how comfortable it is, this immediately gave the LS 400 a clear advantage. There were other performance limitations, too, with the first being the added weight.
Around 200 pounds were added to the Q45’s frame by the system, which went a fair way to blunting performance, even if its suspension setup was improved. Plus, the heavy-duty pump that allowed the system to function worked off the engine, so it sapped between three and six horsepower from the peak output. Fuel economy was also affected, due to the engine having to work harder thanks to the extra weight and running the pump.
Then we come to the subject of cost. Whereas Lexus charged $1,500 for air suspension on the LS 400, Infiniti demanded a full $4,000–5,000 to have the Q45’s active suspension setup fitted. Given the drawbacks outlined above, it’s not hard to see why the brand struggled to sell many of its cars equipped with the contraption.
While exact numbers are impossible to pin down, the fact that so few remain for sale, and that the system was discontinued after only five years, suggests most buyers elected to skip that particular box.
Why a Surviving Q45a for Under $15,000 Might Be the Bargain of the Decade
1989 Infiniti Q45 Selection PackageInterior
Considering how few Q45as were produced, getting one on your driveway in 2026 will be pretty tricky. They are out there, but you’ll have to be content with getting an example with well north of 100,000 miles on the clock. Plus, getting parts for that complicated hydraulic setup will not only be difficult, but also very expensive. Still, the Q45a is holding its value decently well, with the average used value sitting at around the $15,000 mark right now.
Decent deals are out there, though, as illustrated by a white 1994 specimen sold through Bring A Trailer in February 2025. Equipped with far more creature comforts beyond the active suspension – including power-adjustable heated leather seats, a Bose stereo, and automatic climate control – the vehicle showed just 66,000 miles on the odometer when it sold at auction. The Q45a managed to attract a final sale price of $11,237, which is pretty cheap for such a capable luxury sedan.
Infiniti’s gamble with the Q45 failed to pay off, and it was instead left to eat Lexus’ dust. Spin the clock forward 35 years, and not much has changed in this regard. Still, even if the Q45a wasn’t able to become the primary Japanese contender to challenge the mighty Germans, it at least remains an interesting footnote in the great 1990s full-size luxury sedan battle.
Sources: Infiniti.
