Lexus gave us a 2018 Lexus RX450h for the week, so we wanted to put it to the test. Not only did we send it through our Slip Test, designed to test AWD systems, but we also took it up in the mountains for some snowy fun.
The Lexus 450h uses a rather interesting hybrid system to achieve power at all wheels. Up front, there is a 3.5L V6 engine paired with two electric motors. One electric motor right behind the gas V6, and one electric motor at the rear axle. This means there is no direct link between the gas V6 and the rear axle. The back wheels are powered by electricity only.
Total power output is 308 lb-ft of torque, and the EPA says this RX will get 31 MPG city and 28 on the highway. This is, then, the most powerful and most efficient Lexus RX you can buy.
The Slip Test
We wanted to get a good look at how this AWD system works, so Tommy busted out the TFL Slip Test to see what the Lexus can do. This test is designed in a way that we can remove traction from any one wheel. We are then able to see very clearly how well an all wheel drive system can find the wheel with traction, and deliver power to that wheel.
The Lexus’ biggest downfall in this area is the fact that a large majority of its power, the V6 gas engine, cannot send power anywhere but the front wheels. So, when the front wheels lose traction, the amount of power available to the system decreases drastically.
Nathan and Mike headed up to the mountains to see how the system performed in the real world. Fortunately, winter has started to arrive in Colorado. With 4-5 inches of fresh snow on the ground, we could truly test the hybrid AWD system.
Snow performance is largely determined by tires. This Lexus was fit with Bridgestone Ecopia tires. They are not dedicated snow tires, though they are mud and snow rated.
In the fresh snow, Nathan and Mike were quite impressed with the AWD system. It actually did a good job of motivating the Lexus in some tricky conditions. However, turn off traction control and you will be giving a lesson in plowing.
To see more AWD testing, stay tuned to TFLcar.com. Also be sure to watch the whole video to see some not-so donuts and the TFL Slip Test in action.