Lexus RX 450h

The Lexus RX 450h – The First Full Hybrid Luxury-Utility Vehicle

The Lexus RX hybrid (formally the 400h) made history when it was introduced in 2005 as the first full hybrid luxury-utility vehicle. The vehicle was unveiled at the North American International Auto Show in 2004 and it was released for sale in the United States in the middle of 2005. There were over 9,000 pre-orders for the Lexus RX 400h when it launched. When it went on sale it became the first production premium hybrid vehicle on the market. It was later upgraded in 2009 when Lexus introduced a larger engine, also changing the name from the RX 400h to the current RX 450h.

Lexus 450h

The Lexus RX 400h

Compared to the other Lexus luxury-utility vehicles, the RX 330 and the RX 350, the RX 400h featured rounded foglights, a different front grille, and also different LED taillights. It also featured a hybrid information display on the navigation screen which showed the gasoline engine, electrical motor, and regenerative braking activation in real time. The models without navigation screens showed the information on a small monochrome display that was located on the instrument panel.  The RX 400h came exclusively with brushed aluminum interior accents instead of the wood trim that was offered in the standard RX. In 2006 it was also available with Bird’s Eye Maple wood trim.

Lexus 450h interior

The original RX 400h was all-wheel drive and had an MSRP of $49,185 for the base model. A front-wheel drive version was released in 2006 and had an MSRP of $1,400 less than the all-wheel drive model. In 2007, along with the reduction of the federal hybrid tax credit, Lexus lowered the base price of the RX 400h to $42,580 and $41,180 respectively for the all-wheel drive and front-wheel drive versions.

The gasoline engine in the RX 400h was a 3.3-liter V6 that produced 208 horsepower. It was aided by two electric motors, one that was connected to the CVT gearbox and powered the front wheels and the other which powered the rear wheels. They produced 165 and 67 horsepower respectively. The entire system, referred to as Lexus Hybrid Drive, produced a maximum of 268 horsepower. During regular driving conditions only the gasoline engine and the front motor were being used. The rear motor only kicked in when the front wheels lost traction or under full-throttle acceleration.

When stationary, driven at slow speeds (under 40 mph), or decelerating the gasoline engine would switch off automatically. The hybrid drive not only gave the RX 400h improved gas mileage over the RX 300 and RX 350, but it also allowed the vehicle to go from 0-60 mph in 7.3 seconds. That was faster than the gasoline only RX models. Although it did qualify as a super ultra low emission vehicle in the U.S., it consumed roughly the same amount of gas as a compact four-cylinder sedan.

The Lexus 400h was one of only four SUVs to make it on to J.D Power and Associates’ 2006 Automotive Environmental Index of the top 30 most environmentally friendly vehicles. They also awarded the RX 400h the top spot for entry-luxury SUVs in its 2005 Automotive Performance, Execution, and Layout Study on owners’ attitudes towards new vehicle designs. In 2005 at the GreenFleet Awards in the United Kingdom, which recognize environmentally friendly transportation, Lexus was recognized for introducing the RX 400h with the ‘4X4 Manufacturer of the Year’ award.

The RX 450h

The RX 450h was introduced in 2009 as a 2010 model year vehicle. It featured an upgraded 3.5-liter V6 engine, which produced 245 horsepower, and a new inverter which boosted the vehicles total horsepower to 297. The RX 450h had three electric motors including two dual motors for the front wheels and a third electric motor for the rear wheels on the all wheel drive models. The engine now runs on the Atkinson cycle, for added efficiency, as opposed to the previous engine which ran on an Otto cycle system. The Atkinson cycle has a lower compression ratio and a high expansion ratio inside the engine cylinders which allows the system to use less energy to form fuel-air mixtures and release more energy.

Additionally, two other systems are added to the RX 450’s Lexus Hybrid Drive powertrain; an exhaust heat recovery system that reduces the engine warm-up period, and a cooled exhaust gas-recirculation system to reduce fuel pumping loss. Likewise, the electric motors use the first automotive application of liquid cooling on both sides of the high-current transistors. This allows for a larger contribution from the electric motors.

According to the EPA, the fuel efficiency of the RX 450h increased by 20 percent over the RX 400h. In 2009 it was certified with an estimated fuel economy of 32 mpg city and 28 mpg highway. The powertrain is linked to an instrument panel ‘Eco’ light indicator so the driver can monitor their fuel efficiency as it correlates to their acceleration.

The Current RX 450h

Not much has changed under the hood in the last few years, but Lexus did give the RX 450h a facelift in 2012 with new wheels, new head and tail lamps, a new grille, and updated interior colors. New LED running lights were also introduced. The new model uses the Lexus Enform telematics system that includes the Safety Connect SOS system and Shazam tagging.

Lexus 450h console

The RX has won countless awards and is certainly at the top of its class of hybrid SUVs. Kelley Blue Book has dubbed it the luxury utility vehicle with the best resale value and it has been given many top safety ratings. There is no doubt that Lexus will continue impressing consumers with their dedication to fuel economy as well as comfort and safety.

Read previous reviews of the Lexus RX hybrid here.

You can visit the official RX 450h website here.

More Hybrid SUVs:

Hybrid Ford Escape
Hybrid Toyota Highlander
Hybrid Lexus RX 400h
Hybrid ML450



XV Crosstrek

NX 300h
CT 200h
Hybrid Mercury Mariner
Hybrid Mazda Tribute
Hybrid Saturn Vue

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