You probably drive past a dozen of these on your way to work -- some hybrid, some not, some new and some old -- and never take a second glance. That is, unless you're lucky enough to find yourself sitting inside of one and enjoying its comfortable ride, reliable performance, and well-thought-out amenities. Even then, the RX seems a bit like a practical decision, not a passionate one. It's a smart choice, if not a sexy one.
This 2014 Lexus RX 450h sits at the top of the model's totem pole, promising the most power, the most efficiency, the quietest cabin, and the best tech that the current RX platform has to offer. While it doesn't draw attention to itself, doesn't overwhelm or overcompensate, the RX 450h is spacious, refined, and comfortable. And over the course of my testing the SUV gave me a few little "A-ha!" moments and even managed to surprise me at a few turns.
Nearly silent, only kind of efficient
Let's start in the engine bay, which is where the RX 450h differs the most from the rest of the RX lineup. Under a sea of plastic engine covers designed to muffle power-train noise and keep you from mucking around with the oily bits, you'll find a 3.5-liter V-6 gasoline engine that is inseparably mated to a 116 kW electric motor via a continuously variable transmission. The combo works together to get you a maximum of 295 available horsepower.
Our all-wheel-drive variant adds a second 50-kW electric motor on the rear axle to drive the rear wheels on demand with power stored in the RX's NiMH battery pack under the back seats. This drive-by-wire setup eliminates the need for a fore-t0-aft driveshaft, thus saving weight and allowing the SUV to do without a hump in the second-row foot space. Being electric, the torque to the rear axle is instantaneous when needed for accelerating or gripping. As the car's a hybrid, the rear electric motor doubles as a generator when not in use, grabbing extra energy during regenerative braking to charge the battery pack.
Lexus doesn't officially state a torque number for the RX hybrid, claiming that the hybrid's twisting force can't so simply be derived, which is frustrating for those checking the specs. However, the RX 450h feels like it has plenty of pound-feet at its disposal when the time comes to accelerate.
One of the best benefits of the Lexus hybrid system doesn't show up on the spec sheet. The SUV is extremely quiet in its operation, which you'd expect when running fully under electric power, but even when the gasoline engine fires up for freeway cruising or when working with the electric motors to accelerate away from a traffic light at a reasonable speed, the RX is quite quiet. That the gasoline engine's transition from stopped to running is nearly imperceptible helps a lot with that feeling of refinement.
If there is a trade-off to the smooth, silent hybrid system, it's a lack of pedal feel. While the hybrid likes a light foot, it has a tendency to smooth out pedal input, which is good for fuel economy, but can create a slight lag when you need a quick squirt of power for a pass. I suppose that between the CVT and the hybrid system's gas-electric handoff, there's a lot of wiggle room between my foot and the rubber meeting the road.
Give it the beans for a quick stoplight drag race and RX does not disappoint with its acceleration. There's no drama and no wheelspin, just a brief surge of electric torque before the engine joins the chorus with plentiful power. Because the CVT holds its ratio, there's no jerking or interruption of power for shifting, but it also means that the engine holds a single Hoover-like induction note. Guilt over being so wasteful with fuel in your Lexus hybrid will have you lifting before the noise gets too annoying.
The CVT features Sport and manual shift modes, so the CVT can shift between fixed ratios with the flick of the shift knob, but you'll probably never use it -- especially without paddle shifters. You may, on the other hand, use the EV mode when the finicky setting will allow it.
Fuel economy for the 2014 RX 450h is stated by the EPA at 30 city, 28 highway, and 29 combined, but I was only able to do 25.4 mpg despite my best efforts at a light right foot. (I promise, I only did one or two zero-to-60 runs during my entire week with the RX.)
Refined, but not revolutionary
The RX's cabin is filled with little nice touches that elicit a grin here and an exclamation there. I particularly like how the power windows slow down for the last few inches of their travel, closing silently rather than thunking shut. It's that sort of consistent attention to detail that really makes me appreciate Lexus as a luxury marquee.
The whisper-quiet power train and excellent noise and wind deadening allow the optional Mark Levinson audio system to shine unmolested, creating the best possible conditions for it to deliver one of the great mobile listening experiences. The smooth ride was a bit floaty, but did an excellent job of isolating me from the imperfections of the road. Meanwhile, our optional Premium Leather and matte bamboo trim was praised by all who spent time in the cabin.