The Lexus RX 450h Hybrid, and before it the RX400h was one of the first hybrid-powered crossover SUV’s on the market. Back then and now, it comes with a powertrain that actually bucks the trend of hybrids and is quite powerful, if not fast.
It all starts with an Atkinson Cycle version of the Toyota-Lexus corporate 3.5 liter V6, this one with direct fuel injection. It’s good for 259 horsepower on its own, but it’s joined by two electric motors in the continuously variable transmission.
Of the two, the main electric drive motor provides 165 horsepower. It can operate the RX450h under electric only power with no sweat provided its batter has the juice. When combined with the gasoline engine, the two can belt out 308 total system horsepower.
Our tester here was a front-wheel drive model, but you can option all-wheel drive which provides an electric motor drive at the rear axle, that one with an additional 67 horsepower. It doesn’t raise the total system horsepower however, just allows the computer to manage power differently and give you more traction.
On an interesting product strategy note, the less expensive Toyota RAV4 Hybrid that uses similar hardware comes standard with all-wheel drive where here in the $50,000 plus Lexus it’s an option.
And to hardware, as we look around the engine bay you can see a few interesting bits and pieces. The high-voltage hybrid electric controller, always a significant piece of hardware is located up front ahead of the driver and under some other equipment.
Also fascinating is the brake-by-wire system found up ahead of the passenger. The Lexus RX was one of the first mass-production vehicles to have brake-by-wire in which the brake pedal acts as an electric controller, the computer actually handling the hydraulic actuation. There is a mechanical backup however should the electrical system fail.
And that gets us to routine service locations. The brake fluid reservoir is therefore on the passenger side over the brake-by-wire hardware. The windshield washer fluid is up ahead of that, and the engine oil fill and dipstick are where you expect them – on the engine.
On the driver side you will find the fuse panels neatly arranged and the coolant reservoir is up on the firewall where you would normally expect to find the brake fluid.
Of note here the air filter box is one of the newer cartridge style designs that allows for very easy check and replacement. You simple pull the clips and slide it out. There’s no wrangling with a clumsy air box and other items you need to squeeze your hands around.
The 12-volt starter and accessory battery you might have notice is missing in action from the engine bay, you will find it back in the rear under the cargo floor. The Nickel Metal Hydride batter for the electric drive is mounted under the rear passenger seat.
