Compare the2022 Acura RDXVS 2021 Mercedes GLB

The Acura RDX has standard driver and front passenger side knee airbags mounted low on the dashboard. These airbags helps prevent the driver and front passenger from sliding under their seatbelts or the main frontal airbags; this keeps them better positioned during a collision for maximum protection. Knee airbags also help keep the legs from striking the dashboard, preventing knee and leg injuries in the case of a serious frontal collision. The GLB doesn’t offer a front passenger side knee airbag.

The RDX’s standard lane departure warning system alerts a temporarily inattentive driver when the vehicle begins to leave its lane and gently nudges the vehicle back towards its lane. A lane departure warning system costs extra on the GLB.

To help make backing out of a parking space safer, the RDX’s standard rear cross-path warning system uses sensors in the rear bumper to alert the driver to vehicles approaching from the side, helping the driver avoid collisions. The GLB doesn’t offer a cross-path warning system.

Both the RDX and the GLB have standard driver and passenger frontal airbags, front side-impact airbags, driver knee airbags, side-impact head airbags, front seatbelt pretensioners, front wheel drive, height adjustable front shoulder belts, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, daytime running lights, blind spot warning systems, rearview cameras, available all wheel drive and around view monitors.

For its top level performance in IIHS driver and passenger-side small overlap frontal, moderate overlap frontal, side impact, roof strength and head restraint tests, its standard vehicle-to-vehicle front crash prevention system, its standard vehicle-to-pedestrian front crash prevention system, and its standard headlight’s “Good” rating, the Insurance Institute for Highway Safety grants the RDX its highest rating: “Top Pick Plus” for 2021, a rating granted to only 68 vehicles tested by the IIHS. The GLB has not been tested, yet.

Acura’s powertrain warranty covers the RDX 2 years and 20,000 miles longer than Mercedes covers the GLB. Any repair needed on the engine, transmission, axles, joints or driveshafts is fully covered for 6 years or 70,000 miles. Coverage on the GLB ends after only 4 years or 50,000 miles.

J.D. Power and Associates’ 2021 survey of the owners of three-year-old vehicles provides the long-term dependability statistics that show that Acura vehicles are more reliable than Mercedes vehicles. J.D. Power ranks Acura 10th in reliability, above the industry average. With 14 more problems per 100 vehicles, Mercedes is ranked 15th.

The RDX’s 2.0 turbo 4-cylinder produces 51 more horsepower (272 vs. 221) and 22 lbs.-ft. more torque (280 vs. 258) than the GLB’s 2.0 turbo 4-cylinder.

As tested in Motor Trend the Acura RDX is faster than the Mercedes GLB:

To lower fuel costs and make buying fuel easier, the Acura RDX uses regular unleaded gasoline (premium recommended for maximum performance). The GLB requires premium, which can cost 20 to 55 cents more per gallon.

The RDX has 1.2 gallons more fuel capacity than the GLB (17.1 vs. 15.9 gallons), for longer range between fill-ups.

The RDX has a standard cap-less fueling system. The fuel filler is automatically opened when the fuel nozzle is inserted and automatically closed when it’s removed. This eliminates the need to unscrew and replace the cap and it reduces fuel evaporation, which causes pollution. The GLB doesn’t offer a cap-less fueling system.

In its Green Vehicle Guide, the U.S. Environmental Protection Agency (EPA) rates the Acura RDX higher (6 out of 10) than the Mercedes GLB (5). This means the RDX produces up to 6.9 pounds less smog-producing pollutants than the GLB every 15,000 miles.

A 10-speed automatic is standard on the Acura RDX, for better acceleration and lower engine speed on the highway. Only an eight-speed automatic is available for the GLB.

The RDX stops shorter than the GLB:

For better traction, the RDX A-Spec’s tires are larger than the largest tires available on the GLB (255/40R20 vs. 235/55R18).

The RDX A-Spec’s tires provide better handling because they have a lower 40 series profile (height to width ratio) that provides a stiffer sidewall than the GLB’s optional 45 series tires.

For better ride, handling and brake cooling the RDX has standard 19-inch wheels. Smaller 18-inch wheels are standard on the GLB.

The RDX has a standard easy tire fill system. When inflating the tires, the vehicle’s integrated tire pressure sensors keep track of the pressure as the tires fill and tell the driver when the tires are inflated to the proper pressure. The GLB doesn’t offer vehicle monitored tire inflation.

The RDX AWD has a standard space-saver spare (not available on FWD/A-Spec) so you can replace a flat tire and drive to have the flat repaired or replaced. A spare tire isn’t available on the GLB; it requires you to depend on its run-flat tires, which limits mileage and speed before they are repaired. If a run-flat is damaged beyond repair by a road hazard your vehicle will have to be towed. Some tire options on the GLB don’t have a run-flat feature, either.

For better handling and stability, the track (width between the wheels) on the RDX is 1 inch wider in the front and 1.5 inches wider in the rear than on the GLB.

For greater off-road capability the RDX has a greater minimum ground clearance than the GLB (8.2 vs. 7.9 inches), allowing the RDX to travel over rougher terrain without being stopped or damaged.

The RDX uses computer-generated active noise cancellation to help remove annoying noise and vibration from the passenger compartment, especially at low frequencies. The GLB doesn’t offer active noise cancellation.

The RDX has .5 inches more front legroom, 3.8 inches more front shoulder room, .3 inches more rear legroom and 1.7 inches more rear shoulder room than the GLB.

The RDX has a much larger cargo volume with its rear seat up than the GLB with its rear seat up (31.1 vs. 5.1 cubic feet). The RDX has a much larger cargo volume with its rear seat folded than the GLB with its rear seat folded (79.8 vs. 62 cubic feet).

Pulling a handle automatically lowers the RDX’s rear seats, to make changing between passengers and cargo easier. The GLB doesn’t offer automatic folding seats.

The RDX has a 1500 lbs. towing capacity. The GLB has no towing capacity.

To improve rear visibility by keeping the rear window clear, the RDX has a standard rear fixed intermittent wiper with a full on position. The rear wiper standard on the GLB only has an intermittent setting, so in a hard rain visibility isn’t as good.

Consumer Reports rated the RDX’s headlight performance “Good,” a higher rating than the GLB’s headlights, which were rated “Fair.”

To shield the driver and front passenger’s vision over a larger portion of the windshield and side windows, the RDX has standard extendable sun visors. The GLB doesn’t offer extendable visors.

The RDX has standard heated front seats. Heated front seats cost extra on the GLB. The RDX Advance also has standard heated rear seats to keep those passengers extremely comfortable in the winter. Heated second row seats aren’t available in the GLB.

The Car Book by Jack Gillis recommends the Acura RDX, based on economy, maintenance, safety and complaint levels.