Nissan’s luxury brand Infiniti adds a third SUV this year with the compact QX30, which rides and looks more like a small hatchback.

The 2017 Infiniti QX30 also has an unusual pedigree. Built at a Nissan factory in England and, in a deal with German luxury carmaker Mercedes-Benz that helped reduce Infiniti’s costs, the QX30 uses the underlying vehicle platform, turbocharged four-cylinder engine, transmission and many other components of the compact Mercedes GLA 250 SUV.

Even the QX30 name – QX denotes an SUV in Infiniti’s dictionary – has a story behind it. Infiniti originally planned to sell both a Q30 hatchback and a QX30 SUV but instead opted for the QX30 name in the U.S., even for the SUV that rides closest to the ground like a hatchback.

The five-seat, 2017 QX30, which has a starting manufacturer’s suggested retail price, including destination charge, of $30,945 for a front-wheel drive base model, undercuts the 2017 GLA’s base price of $ 33,775.

The difference is in the details. The QX30 has cloth-covered seats, six-speaker audio system, rearview monitor, 7-inch information display, eight air bags and manually adjusting front seats. Meanwhile, the base two-wheel drive GLA comes standard with faux leather seat upholstery and power-adjusting driver’s seat, among other things.

The lowest starting retail price, including destination charge, for a 2017 QX30 with all-wheel drive is $35,395 - about $400 less than a base, 2017 GLA 250 4Motion model.

All QX30s have Mercedes’s capable 2-liter, turbocharged four-cylinder that generates 208 horsepower and Mercedes’ seven-speed, dual-clutch transmission that a driver can operate like a regular automatic.

The QX30’s exterior styling is avant garde for an SUV: a stylized rearmost steel pillar at the edges of the rear window and an abrupt rear end. Roof rails, which typically are a key styling cue for SUVs, aren’t even options on three trim levels.

The test vehicle, a QX30 Sport priced at $43,735, was just 2.4 inches taller than a Honda Civic, and driver and passengers dropped down to get into the seats, as they would in a hatchback car.

The engine spun up nicely, particularly in Sport driving mode, where the electronic engine management kept the revs up so the turbo power was at the ready. In contrast, in the economy drive mode showed noticeable turbo lag during acceleration.

Torque peaks at 258 foot-pounds starting at 1,200 rpm and going to 4,000 rpm. This power pushed passengers back into their seats and made the tires squeal in the front-drive QX30 tester.

As in the GLA, the QX30’s engine turns off when the vehicle idles and the driver fully depresses the brake pedal, but the QX30 tester shuddered often when the engine automatically started back up - a roughness one wouldn’t expect in a $40,000-plus vehicle.

The ride was rough, too, in part because of 19-inch run-flat tires that were on the Sport model. Passengers felt vibrations even on smooth-looking pavement. Manhole covers and cracked roadways seemed to jostle passengers, and long drives could be fatiguing.

Road noises and sounds from nearby cars readily intruded, and the QX30 had so much wind noise above 45 miles per hour that the driver checked to make sure the window was fully closed.

Black seats in the Sport model were attractively trimmed in Nappa leather, with white stripes and white accent stitching. But seat cushions, particularly in the back seat, were short and lacked good thigh support.

It was annoying to manually unlock the QX30 driver door to exit the vehicle; the owner’s manual did not highlight a way to program the vehicle to automatically unlock the door when the car was turned off and the key was removed from the ignition.

Fit and finish wasn’t the best, as the memory seat button module had a cheap feel and deflected into the door whenever it was used.

Lackluster fuel mileage for a front-wheel drive vehicle combined with a small 13.2-gallon gasoline tank to provide a driving range of just 315 miles before the test vehicle needed a fill up of pricey premium gas.