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Mercury MountaineerModel year report

2006 Mercury Mountaineer Problems

Complaints
117filed with NHTSA
Median mileage
58,849miles, 94 complaints with mileage
Recalls
1campaigns on record
Trend
FallingComplaints filed in the last 3 full calendar years are at least 25% lower than in the 3 years before.
NHTSA crash rating
—overall rating starts with 2011 models
EPA fuel economy
16 mpgcombined, 4.0L 6-cyl RWD · 13 city / 19 hwy

Sources: NHTSA records for the 2006 Mercury Mountaineer (complaints, recalls, investigations), NHTSA crash tests, EPA fuel economy. Report an error

What owners report

Complaints on this model year center on two recurring themes: coolant loss from a cracked or leaking radiator, and transmission behavior that owners describe as a hard thud or lurch when slowing to a stop or shifting from park. Most of these reports arrive between roughly 35,000 and 75,000 miles, and a number of owners describe replacing the radiator more than once.

  1. Engine cooling

    Radiator leak or crack / coolant loss

    • 42 complaints (36%)
    • median 58,026 mi at 5.3 yrs old (38 state mileage)
    • 2 mention a crash, fire or injury
    • filed 2009–2022

    Owners describe coolant disappearing from the reservoir, a smell of antifreeze under the hood or inside the cabin, and eventually an overheating temperature gauge or warning light. Several say the radiator was found cracked or leaking at a seam and was replaced, sometimes two or three times, and in some cases the dealer could not find the leak at first. Complaints also describe coolant residue, a low reservoir without a visible puddle, and quotes of several hundred dollars for replacement once the vehicle was out of warranty. Reports in the sample cluster from about 30,000 to 75,000 miles, with some at higher mileage and repeat replacements after only tens of thousands of miles.

    2 related service bulletins

    What to check: Ask for radiator replacement records and check the coolant reservoir level and the radiator seams/side tanks for residue before buying. A service bulletin describes replacement of the lower radiator hose clamps, so ask whether that was done.

    2 excerpts from owner complaints in NHTSA records

    “The radiator keeps leaking, first dealer said there was nothing wrong with the vehicle, I am always putting coolant in the vehicle. You can smell the coolant as soon as you open the hood. This has been an ongoing problem since I had 53,000 miles and now that I have 122,000 miles it is getting worse and has to be repaired again.”

    NHTSA complaint #10551076, filed 2013-11, 53,000 miles

    “I have gone through 3 radiators so far and now I need a 4th. This time, the radiator caused the pumps to start leaking ( which are not serviceable) and eventually ruined my transmission, rendering the truck non-drivable. This problem has cost me thousands of dollar and I want a recall to start on this part with ford.”

    NHTSA complaint #10558560, filed 2014-01, 115,000 miles
  2. Transmission and drivetrain

    Transmission thud or lurch when stopping

    • 37 complaints (32%)
    • median 54,000 mi at 4.1 yrs old (31 state mileage)
    • 4 mention a crash, fire or injury
    • filed 2007–2021

    Owners frequently describe a hard jolt, clunk or thud felt through the vehicle when coming to a stop, as if the vehicle had been struck from behind, and some report a lurch forward or backward when selecting drive or reverse. Many say the dealer reprogrammed the transmission control module, changed fluid or replaced a valve with limited or temporary improvement, and some were told the behavior could not be reproduced. A smaller group reports slipping, delayed engagement, harsh 1-2 and 3-2 shifts, or a transmission that eventually stopped driving. Reported from very low mileage (under 15,000 miles in several cases) up through roughly 100,000 miles, often during stop-and-go driving.

    5 related service bulletins

    What to check: Drive the vehicle through several stops from 35-45 mph and feel for a thud or lurch on downshift, and try park-to-drive and park-to-reverse shifts. Ask whether any transmission reprogramming, valve body work or fluid service was performed and keep records of it.

    2 excerpts from owner complaints in NHTSA records

    “I have just purchased a used 2006 Mercury Mountaineer awd v8. When the vehicle is coming to a stop, the transmission lunges forward as it is downshifting. It feels just like another vehicle has hit my vehicle from behind. This is a dangerous situation since as the vehicle lunges forward, it could hit a pedestrian in a cross walk or hit another vehicle in front of me.”

    NHTSA complaint #10252649, filed 2008-12, 20,784 miles

    “My truck has 115,000 miles on it, transmission is now gone. When I put it in reverse it would jerk back like the it was being hit, all of sudden it started dragging while driving, and having problems shifting into gear, and now its totally gone...only had the vehicle two years.”

    NHTSA complaint #10292241, filed 2009-11, 115,584 miles

Summary written with AI from a sample of 60 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Where a problem shows a complaint count, every complaint for this model year was matched with fixed keyword rules (written with AI and tested against the sample), and the mileage, age and repair figures are calculated from those complaints; owners' figures are as stated, not verified. Other counts refer to the sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.

NHTSA recorded 117 consumer complaints for the 2006 Mercury Mountaineer. 94 of the complaints include a mileage, and 34% of those were filed for vehicles with under 50,000 miles; the median is 58,849 miles. Of all complaints, 6 involved a crash, 2 a fire, 7 an injury, according to the filers. NHTSA lists 1 recall campaign and 37 technical service bulletins for this model year.

Not compared (before 2008). Model years 2008–2023 of the same vehicle that have at least 25 complaints are compared, and a model needs at least 3 of them.

Which parts are reported most

Complaints can name more than one part, so the counts add up to more than the total. Select a part to see its complaints, recalls and bulletins.

Also reported: Equipment (2), Exterior lighting (2), Tires (2), Wheels (2), Air bags (1), Seat belts (1), Steering (1), Suspension (1), Visibility (wipers, defrost, mirrors) (1).

Example complaints

Engine cooling: “Leaky radiator was 1st detected by myself but mechanics were unable to determine the leak because anti-freeze was not visibly leaking but the resevoir was always empty. I was told it was a problem with my tires. The problem was not addressed by mechanics until they saw that the radiator could not hold coolant any longer. Now it has been identified as having a hole in the radiator.”

NHTSA complaint #10302488, filed 2010-01, 69,543 miles

Transmission and drivetrain: “The gear shaft will stop my car from starting when I turn it off. It will also make my car vut off while driving..the button on the gear stick will get stuck and I am able to shift gears...when the car is not started and my foot is not on the breaks. Even when the button is not stuck, it still will get stuck in park and wont let me start my car..a recall should be started..because I have seen others on here with similar complaints..so its a manufacturing accident not the consumer.”

NHTSA complaint #11194823, filed 2019-04, 166,000 miles

Engine: “I purchased this vehicle recently with only 40,000 miles. The car keeps stalling or dying as you may say as I drive. It will be okay for a short period of time and then just die right on the highway! Once it dies once, the car will continue to do so over and over again until the engine has cooled down. I have the engine codes of p2104, p2111 and p2135 with a refere to p2101. I have brought it to several mechanics and paid well over $1,000 to fix this problem and it just continues. I am afraid my family may all die! …”

NHTSA complaint #11022125, filed 2017-09, 42,000 miles

Electrical system: “Shortly after purchasing my Mountaineer the electric running board on the driver side began to make a grinding sound. Bought from a dealer in wa state and moved to wi state where the driver side stopped and the passenger side stopped extending/retracting. Moved to nj and we had purchased the vehicle extended warranty. Began to sound like a knocking sound with little power and had towed to dealer. There they found all 8 spark plugs fouled, driver side had 3 exhaust manifold bolts loose. …”

NHTSA complaint #10790375, filed 2015-11, 120,000 miles

Mileage when problems were reported

34% of the 94 complaints with a mileage were filed for vehicles with under 50,000 miles; the middle half falls between 40,000 and 86,546 miles.

7%0–107%10–2519%25–5033%50–7515%75–10014%100–1504%150+
Share of complaints by mileage when the problem was reported, in thousands of miles (94 complaints with mileage). Red bars: under 50,000 miles. Bucket widths differ. Median: 58,849 miles.

Complaints by year filed

Trend: falling. Complaints filed in the last 3 full calendar years are at least 25% lower than in the 3 years before.

’07’09’1124’13’15’17’19’22
Complaints by year the complaint was filed with NHTSA. Red bars: the last 3 full calendar years used for the trend. The current year (2026) is partial.

Crash test ratings

NHTSA's 5-Star Safety Ratings for the 2006 Mercury Mountaineer. Frontal results are shown driver / passenger; rollover shows the star rating and NHTSA's estimated risk of rolling over in a single-vehicle crash.

VersionOverallFrontalSideSide poleRollover
Mountaineer · sedan RWD/AWDnot rated5 / 5——3 · 22.8% risk

Ratings before the 2011 model year come from an older, less demanding test and are not comparable with ratings for 2011 and later.

Source: NHTSA New Car Assessment Program (5-Star Safety Ratings), nhtsa.gov/ratings.

Fuel economy and running cost

EPA ratings for each 2006 Mercury Mountaineer version. Annual fuel cost is the EPA's estimate at its current fuel prices for 15,000 miles a year (55% city driving).

VersionEngineTransmissionCityHwyComb.Fuel / yr
Mountaineer 2WD4.0L 6-cyl5-speed automatic131916$4,200
Mountaineer 2WD4.6L 8-cyl6-speed automatic131915$4,450
Mountaineer 4WD4.0L 6-cyl5-speed automatic131915$4,450
Mountaineer 4WD4.6L 8-cyl6-speed automatic131815$4,450

Source: U.S. EPA and Department of Energy, fueleconomy.gov. Ratings are for comparing vehicles; real-world mileage varies with driving and conditions.

Recalls and investigations

Recall details for the 2006 Mercury Mountaineer → · Check a VIN at nhtsa.gov/recalls

Technical service bulletins

TSBs are manufacturer notes to dealers about known repair procedures. They are not recalls and do not by themselves mean a vehicle has a fault. 37 on record; the latest 10 are shown.

See all 37 bulletins →

Other model years of the Mercury Mountaineer

YearComplaintsMedian miRecallsCrash ★MPGScore (50 = typical)Trend
20101338,6601—17—Not enough data
2009647,0000—17—Not enough data
20089665,8001—16Not compared (fewer than 3 comparable model years)Falling
20078175,0000—16Not compared (before 2008)Rising
200611758,8491—16Not compared (before 2008)Falling
20058256,7500—15Not compared (before 2008)Rising
200421068,0000—16Not compared (before 2008)Falling
200315278,7840—16Not compared (before 2008)Falling
200237275,0002—16Not compared (before 2008)Falling
20012275,0003—17—Stable
200012370,0006—16Not compared (before 2008)Rising
199915170,0007—16Not compared (before 2008)Stable
199823685,0005—16Not compared (before 2008)Stable
1997328124,0006—14Not compared (before 2008)Falling

All Mercury Mountaineer model years · Best and worst years by complaints

Frequently asked questions

What are the most common problems with the 2006 Mercury Mountaineer?

Complaints on this model year center on two recurring themes: coolant loss from a cracked or leaking radiator, and transmission behavior that owners describe as a hard thud or lurch when slowing to a stop or shifting from park. The issues reported most often: Radiator leak or crack / coolant loss; Transmission thud or lurch when stopping.

How many NHTSA complaints does the 2006 Mercury Mountaineer have?

NHTSA recorded 117 consumer complaints for the 2006 Mercury Mountaineer as of Oct 29, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate.

What part of the 2006 Mercury Mountaineer is reported most often?

Engine cooling is named most often, in 43 complaints (37% of the total), followed by transmission and drivetrain with 39.

Has the 2006 Mercury Mountaineer been recalled?

NHTSA lists 1 recall campaign for this model year. To check a specific vehicle, enter its VIN at nhtsa.gov/recalls.

What gas mileage does the 2006 Mercury Mountaineer get?

The EPA rates the 2006 Mercury Mountaineer (Mountaineer 2WD, 4.0L 6-cyl) at 16 mpg combined, 13 city and 19 highway, with an estimated annual fuel cost of $4,200 at 15,000 miles a year. Other engine and drive versions are rated differently.

At what mileage are problems with the 2006 Mercury Mountaineer reported?

Among the 94 complaints that include a mileage, the median is 58,849 miles and the middle half falls between 40,000 and 86,546 miles; 34% were filed for vehicles with under 50,000 miles.

About this data. Data from NHTSA (ODI) complaints, recalls, TSBs and investigations, updated Oct 29, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate. Crash ratings are from NHTSA’s New Car Assessment Program. Fuel economy is from the EPA and DOE (fueleconomy.gov).

Complaint counts come from NHTSA’s public complaint database; we count each complaint once. The source records for this vehicle are on nhtsa.gov. Scores and trends are our own summaries of that data, described in the methodology. This page is not legal, safety or repair advice: for a specific vehicle, check its VIN at nhtsa.gov/recalls and ask a qualified mechanic. See an error? Tell us.