This page covers 3 recalls, 278 owner complaints and EPA fuel economy for the 2010 Mercury Mariner.
22–32 mpg combined
7.4–10.7 L/100km
Sport Utility Vehicle - 2WD
Fuel economy data from fueleconomy.gov (EPA / U.S. Dept. of Energy). Annual cost based on 15,000 mi/yr at 55% city driving and current fuel prices. MPG is U.S. gallons; L/100km converted. Ranges reflect the 4 tested variants for this model year.
Steering and speed control dominate the complaint picture for the 2010 Mercury Mariner. The most-reported issue by far involves the electric power steering system, owners frequently describe a "Power Steering Assist Failure" warning appearing on the dash, followed by the steering wheel becoming very heavy or difficult to turn, sometimes while the vehicle is moving. Some describe the steering feeling locked or unresponsive at low speeds. The vehicle speed control system draws nearly as many complaints, with owners reporting hesitation, bogging, or the vehicle struggling to accelerate as expected. Powertrain complaints round out the top three, covering a range of driveability and engine performance issues. The power steering failure pattern is the clearest recurring theme, with owners consistently describing sudden loss of assist with little or no prior warning.
278
Total Complaints
3
Crash-Related
2
Fire-Related
3
With Injuries
By System
The 2010 Mercury Mariner has 3 recalls, the most serious being a fuel delivery module on 3.0L engine models that can crack and leak fuel, raising the risk of a fire if the fuel contacts an ignition source.
A separate recall affects front wheel bearings sold as aftermarket service parts during a specific window in 2015. If one of these incorrectly sized replacement bearings was installed, it can interfere with normal braking and steering response, increasing the risk of a crash. On the steering side, the electric power steering system has a torque sensor that may fail to detect driver input and drop the power assist entirely. At low speeds, this can make the steering wheel significantly harder to turn, which is most noticeable during parking maneuvers or slow turns where full effort is required.
At a glance
What can fail
The fuel delivery module may crack on certain 2010-2012 Ford Escape and 2010-2011 Mercury Mariner vehicles with 3.0L engines, causing fuel to leak.
What the fix does
Dealers will replace the fuel delivery module flange with a redesigned version that prevents leaks.
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Complaints are owner-reported and reflect individual experiences, not confirmed defects. They are distinct from recalls. Data sourced from the national vehicle safety complaint database. See trending complaints →
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
The front wheel bearings have incorrect dimensions: 76mm outer width and 39mm height instead of the correct 78mm outer width and 45mm height. These undersized bearings may not fit properly or secure correctly on affected vehicles.
What the fix does
Timken will replace the incorrect wheel bearings with correct ones at no charge. Contact Timken customer service at 1-866-984-6536 to arrange replacement.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
The steering torque sensor may fail to detect your steering input, causing the power steering system to unexpectedly lose assist.
What the fix does
Dealers will update the power steering and instrument cluster software. If fault codes are found, faulty components will be replaced.
Summarized — see the official notice for exact wording, dates, and contacts.
