2016 Range Rover Sport Td6 vs. 2016 BMW X5 40e: Luxury Eco SUV Comparison [Review]

Photos by Derek Mau

The idea that a large luxury SUV can be environmentally responsible is definitely counter-intuitive, if not a genuine head-scratcher. I can remember hearing an especially green-minded friend spit out the phrase “Earth killer!” to a passing Range Rover not too long ago, which is probably what most Prius drivers are thinking when they see one on the road. Which makes this review all the more interesting, as we have not one but two large luxury SUVs making a sincere attempt at shrinking their environmental footprint.

In a somewhat surprising move, given all the recent controversy surrounding diesel emissions, Land Rover is offering a diesel engine in both the Range Rover and Range Rover Sport for the first time this year. The 3.0-liter turbocharged V6 diesel engine provides a 32 percent increase in combined fuel economy compared to the standard supercharged V6 gasoline engine, with almost the same level of performance.

BMW has been offering a diesel engine in the X5 for years, but new for this year is the X5 xDrive40e plug-in hybrid. Combining a 2.0L turbocharged engine with an 111 hp electric motor, the X5 xDrive40e provides comparable performance to an X5 with the standard 6-cylinder engine, while also offering the benefits of electric-only driving.

BMW X5 xDrive 40e

BMW should be commended for trying something quite different with this plug-in hybrid version of the X5. Pairing a small turbocharged engine with an electric motor would not seem like a good idea for a large SUV but in this case, it actually works quite well, so long as the battery has enough charge.

Acceleration is easily on par with the base X5 powered by a turbocharged 6-cylinder engine, and overall system integration is excellent. Select the electric-only mode and you can cruise around silently for up to 14 miles at speeds up to 75 mph. Getting the full range requires an especially delicate right foot, however, as we had a hard time driving more than 10 miles before the gas engine would need to kick-in.

With a depleted battery, the X5 xDrive40e showed its most significant weakness, as relying solely on a small turbocharged engine for thrust — optimistic at best in such a large vehicle. The otherwise peppy little engine is just out of its element towing around a 5,000+ pound SUV that is saddled with a heavy battery and electric powertrain. Fuel-efficiency also suffers, as it registered in the low 20s when running on the gas engine alone.

The extra weight of the powertrain also becomes an issue when it comes to cornering. Sure, a large SUV is unlikely to be nimble, but an X5 has never felt quite this reluctant to want change directions. Even shod with a set of wide and sticky tires, the X5 xDrive40e wants to understeer in tight turns and generally doesn’t encourage the kind of spirited driving that BMW is known for.

As indicated by the “xDrive” moniker, all-wheel drive comes standard, which should appeal to folks looking for a vehicle with all-weather capability. Actual off-road driving is probably not a great idea, given the low-profile performance-oriented tires, but in a pinch, you could probably navigate a dirt road without too much trouble.

The X5 xDrive40e starts at $64,000 and comes quite nicely equipped. Our test car featured a well-appointed cabin with richly upholstered brown leather seats, and a host of available tech and safety features. There is also a $4,585 federal tax credit, which makes the X5 xDrive40e only a few thousand dollars more expensive than a regular X5. Applicable state tax credit may apply in your area.

For someone with a short commute who is also looking for a large, practical vehicle, the X5 xDrive40e is a worthy option. However, with limited electric-only range, and compromised performance when the battery is drained, the X5 xDrive40e seems more like a rough draft than a well-polished finished product.

Land Rover Range Rover Sport HSE Td6

Driving the new Range Rover Sport Td6 is a potent reminder of why diesel engines just make sense for larger vehicles. The 3.0-liter V6 only makes 254 horsepower, but with 440 lb-ft torque available at 1,750 rpm, acceleration is instant and very satisfying, without the high-strung antics of traditional gas engines. Combined with a quick shifting 8-speed transmission, the engine is rarely caught off guard, and also returns excellent fuel efficiency, even when driven quite aggressively.

We managed to achieve 25 mpg over several hundred miles of often less than casual driving, which exactly matches the EPA combined rating. Drive more frugally and you’ll likely see mpg figures in the high twenties, which is quite remarkable for such a large vehicle. The engine also features a selective catalytic reduction system and uses diesel exhaust fluid to reduce NOx emissions, which will hopefully keep the EPA happy.

There is also almost no trade-off in performance, as acceleration is only a few tenths slower than the supercharged 6-cylinder engine that comes standard in the Range Rover Sport. Need to quickly pass that inattentive driver hogging up the left lane? Just push the throttle down a bit more and surf the wave of torque as you effortlessly glide by.

Adding to the driving pleasure is the fact that this modern diesel engine is housed in one of the best large SUVs on the market today. The Range Rover Sport is an extremely well-rounded vehicle that combines capable handling, distinctive exterior styling, and an interior that is easily one of the best in the class. And should you ever really need to go off-road, the Range Rover Sport is unlikely to leave you stranded.

With a starting price of $66,950, the Range Rover Sport Td6 is a bit more expensive than the competition, and with options can easily get close to six figures. Our HSE trim level test car, which featured a Meridian sound system and other premium options, stickered at over $85k. Still, given the level of refinement and the excellence of the diesel powertrain, the Range Rover Sport Td6 is a very compelling choice for the more environmentally conscious driver looking to buy a large luxury vehicle.

The 2016 Range Rover Sport Td6 is quite capable off-road — provided it has the right tires. We have video of Land Rover’s esteemed crossover needing a rescue from deep snow because it was fitted with Eagle all-season tires. Here is a more valid test of its trail capabilities up in the Colorado Rocky Mountains below snow level.