Comparison Test: 2015 BMW X3 xDrive28d vs 2015 Mercedes-Benz GLK 250 Bluetec Diesel

Utility

I’m a firm believer that SUVs need a healthy dose of utility to be worth their salt. Having a highly sensible diesel powertrain is a great start, and largely plays in to the practicality of the vehicle.

Mercedes rates its GLK 250 Bluetec at 9.6 L/100 km city and 7 L/100 km highway, while the BMW claims 8.6 city and 6.9 highway for their X3 28d. In reality, BMW’s estimates are pretty close to what one can expect from their little tractor, whereas the GLK’s ratings seem pessimistic.

With a 2/3 highway and 1/3 back road and urban split, we averaged 6.9 L / 100 km in the X3. On one highway stretch in strictly Eco Pro mode (that modifies the throttle calibration for maximum efficiency) I saw an average of 6.5 L/100 km for a 120 km distance.

The Benz, despite showing only 500 km on the odometer when we acquired it, cruised along sipping only 6.1 L/100 km of diesel. Throughout the entire trip, including hustling through the countryside and sitting in some Toronto traffic, the overall average for nearly 750 km was still in the low 6’s. These astonishing figures are in line with what I achieved last year in the GLK 250 Bluetec and suggest that consistently bettering the government ratings for this car should not be difficult.

2015 BMW X3 xDrive28d cargo area organizer, 2015 BMW X3 xDrive28d cargo area, seating. Click image to enlarge

Range for either ute will be similar and test even the most capacious of passenger bladders. The BMW’s fuel tank is 67 L, the Benz’s is 66.

But utility is about more than just punishing your passengers with long stints between bathroom breaks, it’s about how much space those passengers will have to squirm while cursing the car’s range. Subjectively, the back seat in both the X3 and GLK felt equally comfortable. The tall greenhouse that enables a commanding view for the driver also gives a more open and airy feel to the GLK’s passenger compartment, plus provides more rear headroom.

The BMW is the larger vehicle and on paper bests the Benz in most other dimensions, plus cargo capacity. In reality, the differences are often no more than a few centimetres here and there – hardly noticeable.

The Mercedes comes standard with proper roof racks versus the BMW’s sleeker-looking rails.

The spaciousness of the GLK’s interior is sufficient for a small family’s needs – or perhaps a pair of retirees who’ll rarely use the back seat for passengers anyway – but the comparatively worse fuel efficiency of the BMW will be felt with every fill up, earning the Benz the points for overall practicality.

2015 Mercedes-Benz GLK 250 Bluetec cargo area organizer, cargo area, seating. Click image to enlarge