Differential Unit Problems of Mercury Mountaineer

Mercury Mountaineer owners have reported 19 problems related to differential unit (under the power train category). The most recently reported issues are listed below. Also please check out the statistics and reliability analysis of Mercury Mountaineer based on all problems reported for the Mountaineer.

car image   Differential Unit problem of the 2003 Mercury Mountaineer 1
Failure Date: 03/25/2013

The contact owns a 2003 Mercury Mountaineer. The contact stated that while driving 40 mph, the rear differential made a popping sound. The contact stated that while in reverse, the popping sound was louder. The contact took the vehicle to a local mechanic for a diagnostic test. The mechanic noticed a leak in the rear differential and stated the rear differential needed to be replaced. The contact did not have the rear differential replaced. The failure mileage was 240,000.

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car image   Differential Unit problem of the 2004 Mercury Mountaineer 2
Failure Date: 04/10/2012

The contact owns a 2004 Mercury Mountaineer. While traveling 5 mph in reverse, the contact noticed a thumping sound coming from the rear passenger side of the vehicle. Moments later, the contact noticed that the vehicle would no longer accelerate. The vehicle was taken to the dealer where the rear differential was replaced. The contact stated that the failure was recurring. The current and failure mileages were 143,000.

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car image   Differential Unit problem of the 2002 Mercury Mountaineer 3
Failure Date: 06/02/2010

2002 Mercury Mountaineer awd v8 - approximately January and may 2009 both rear hub bearings went bad at 87,000 and 90,000 miles , both sets of emergency brake shoes were disintegrated when taken off . Rear coil springs are broken . Front differential box has leaked for some time now . Rear end axle seal has been leaking for some time now . Going on 4th set of brakes on front . June 2010 at 109,000 miles transmission finally went out - after acting up from time of purchase at 37,000 miles - it would slip when put in drive at first morning startup and would jerk erratically at low speeds - we have never pulled anything with vehicle .

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car image   Differential Unit problem of the 2003 Mercury Mountaineer 4
Failure Date: 09/07/2009

We purchased a 2003 Mercury Mountaineer approx. 9 months ago and have now discovered that the front differential has gone out. When we did extensive research we found that there was a massive recall between 2002 - 2006 for this manufacturer's defect on Mountaineers, explorers, expeditions and range/lnd rovers. When we contacted Ford motor CO; they said that our particular VIN# did not make the recall list. When I asked how come a manufacture's defect could not make the recall list they said it could be an oversight or just maybe not for that model. I then asked how come the research proved to show that these were defective upon manufacturing and some of them not get recalled they had no answer for me. We now have a vehicle that is inoperative and nobody wants to clarify the problem. We have had 2 estimates both with used parts from a wrecking yard. The 1st estimate was $1350 and the 2nd was $800 and no guarantees since they would be pulling the front differential off of a wrecked vehicle the same year as ours and it could also potentially be defective. We do not have the money for the repairs and now my husband has no transportation to get to work. He does drive my car at the moment but can not carry all of his tools in my vehicle since his is an SUV. We did seek legal council and were informed that we need to file this complaint in hopes that you could force Ford to recall our vehicle and they said we had a very good law suit. If my husband did not have this checked and continued to drive it without knowledge of the problem it could have resulted in the gears locking up and a crash which could have resulted in serious injuries or even deaths. Please advise what our options are.

car image   Differential Unit problem of the 2002 Mercury Mountaineer 5
Failure Date: 01/29/2009

The contact owns a 2002 Mercury Mountaineer. While driving approximately 50 mph, the contact applied pressure to the brakes and heard a grinding sound. He then began to smell something burning and noticed smoke underneath the vehicle. He inspected the vehicle and did not notice any leaking. The following day he noticed an extensive amount of oil on the ground and the vehicle was pulling. The vehicle was inspected by a mechanic and the contact was informed that oil was coming from three different places and traveling to the rear differential. The dealer and the manufacturer have not been notified. The current mileage was 118,169 and failure mileage was 118,000.

car image   Differential Unit problem of the 2004 Mercury Mountaineer 6
Failure Date: 12/07/2008

Our vehicle was purchased in June 2008 at dealership nearby. We were driving home and there was a grinding and popping sound in the rearend of the vehicle. It was me , my husband, 3 mth old and 2 yr old occupying the car. My husband got out of the car and stated to get the babies out of the car in a hurry it was on fire. We got the babies out and ran in to call 911 and the fire dept. The fire was contained and took to a local garage at that time I contacted my auto insurance to see if this was something that would be covered. They sent an auto adjuster out to look at it. Our insurance did help to repair the rear differential. The rear differential had got so hot it exploded causing the fire. Then after the car was repaired we began to have problems again at that time I contacted Ford motor company. They explained they could not replace the car but if I took to a local Ford dealer for diagnostic they may consider repairing. So I did and the whole transfer case has to be replaced and Ford is not paying for the cost. I just don't want this experience to happen to anyone else and to risk their lives just driving this car as a result to a fire. The fire was close to the fuel tank. I don't think this car is safe for us to drive I always have that fear in my mind and worrying about my babies. Now I have this new problem with the vehicle to deal with. I have talked to several people and one particular company that has the same type of vehicles with the same problems. Something really needs to be done about this.

car image   Differential Unit problem of the 2002 Mercury Mountaineer 7
Failure Date: 10/17/2008

I bought this Mountaineer in early 2007 with 62,000 miles on it. From the start it shifted very rough. It has progressively worsened until this week when my wife was driving it would not shift out of second gear at all and was nearly broadsided with four children in the vehicle because she could not move. Took it to a repair shop and was informed that I needed to have the transmission fixed. From other comments I have read this seems to be a fairly common problem with this vehicle. Also had to have the rear differential replaced at around 75,000 miles which seems fairly ridiculous, and a bearing has gone out twice on the same wheel. This vehicle doesn't seem to be built to last.

car image   Differential Unit problem of the 2003 Mercury Mountaineer 8
Failure Date: 02/20/2008

Upon leaving work in the am I started my vehicle and none of my dash gauges were working nor were any of the electric window or the radio. I then called my mechanic who adv me to bring it to him. While I was en route to take my vehicle to him it started making a weird noise like I was in a helicopter and I started smelling this weird smell like oil burning at first it thought they messed up my oil change and I was furious. Upon arriving at the shop he immediately smelled the odor put it up on the lift and found out that my front differential had gone bad. I purchased another one and hi installed it and I took it home because he could not find out what was wrong with the gauges on my way to take it to a dealer I was driving down the road and smoke and was coming from the front and back under my car another driving passing by signaled something was coming from beneath my vehicle and upon that I heard a loud bang popping noise and my vehicle lost power and I had to have it towed back to the mechanic only to find out that again the differential failed. I still do not have my vehicle and the gauges windows and radio still does not work. My mechanic checked all the fuses and adv that there was no problem with them. He did however call a Mercury dealer who adv he has had to change some of the front differentials on other Mountaineers but was not certain as to how many were done.

car image   Differential Unit problem of the 2004 Mercury Mountaineer 9
Failure Date: 02/13/2008

Whining noise coming from rear end (rear differential) of vehicle. It appears that Ford motor company is aware of this problem but are not willing to repair this issue for free. This problem is widespread, over many model years.

car image   Differential Unit problem of the 2005 Mercury Mountaineer 10
Failure Date: 11/27/2007

Rear differential needs replaced. Mechanic said can be dangerous. I see that these Ford/Mercury's have this problem all the time. Cost too much to fix, yet I have wife and kids in that car.

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car image   Differential Unit problem of the 2002 Mercury Mountaineer 11
Failure Date: 03/05/2007

I recently bought a 02 Mercury Mountaineer with 58k miles. A few days after I bought it, I noticed a "groan" from the rear end of the vehicle. I have worked on many vehicles before and it was obvious it was the differential. I planned to have the bearings in the rear end replaced, but after doing some investigation on the internet, I have realized that there are a lot of people that have had this problem and spent a lot of money to get it fixed with no good results. Even with a used car purchase, I think Ford should be embarassed at the fact that I am embarassed for making the purchase of the vehicle. I wish Ford would do the right thing and re-gain our trust in them and fix our vehicles the right way. They have knows since day one that they were not right and have done nothing to fix them. I won't buy another Ford until they do something about this. I know they don't care, but right now I own three fords and they will be the last if this is not rectified. Thanks for listening!!!.

car image   Differential Unit problem of the 2003 Mercury Mountaineer 12
Failure Date: 12/16/2006

The contact owns a 2003 Mercury Mountaineer. While driving 65 mph, the contact noticed smoke coming from the front and rear of the vehicle. She then heard a loud bang and the steering wheel began to shake. The vehicle lost power, but did not shut off. The vehicle was towed. The Ford dealer diagnosed the vehicle as needing the front end differential replaced. The vehicle was repaired, but the failure recurred when the contact picked up the vehicle. Since then, the front end differential has been replaced five times. The Ford dealer was unable to diagnose the cause of the continuous failures of the replacement part. The contact also stated that the rear liftgate is cracked. A valid VIN was unavailable. The current mileage is 64,000 and failure mileage was 60,000.

car image   Differential Unit problem of the 2002 Mercury Mountaineer 13
Failure Date: 10/07/2006

: the contact stated when the vehicle was taken to the dealership to rotate the tires, the mechanic noticed oil leaking from the rear differential seals. No warning light alerted the contact of the leak. The manufacturer was contacted, and informed there was no recall for this problem.

car image   Differential Unit problem of the 2002 Mercury Mountaineer 14
Failure Date: 09/14/2005

I had no warning that the automatic transmission in my 2002 Mercury Mountaineer at 55,000 miles was going out. The o/d light came on flashing and the check transmission light came on flashing. The speed of the vehicle would not accelerate past 20 mph. I immediately took it to the Mercury dealership and they repaired the leaking differential seals in the rear of the vehicle and the pinion seals in the front of the vehicle. They checked the transmission fluid and it was full. After 424. 00 the problem was still there. Took vehicle to transmission specialty shop and the vehicle is in the shop at this hour having the transmission yanked out and repaired. This is my first Ford vehicle and my last. There seems to be a transmission issue regarding Ford/Mercury vehicles and there should have been something done about this long before now.

car image   Differential Unit problem of the 1999 Mercury Mountaineer 15
Failure Date: 04/08/2005

1999 Mercury Mountaineer. Leak in rear differential at 40,000 miles. Replaced pinion seal. At 67,000 miles, a loud, whine emitted from rear axle when driving (regardless of speed) and the mechanic advises us to replace rear differential bearings or entire rear differential. If we don't, we fear the rear axle will fail, causing a crash.

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car image   Differential Unit problem of the 2002 Mercury Mountaineer 16
Failure Date: 09/22/2004

Our 2003 Mercury Mountaineer rear differential needed rebuilding in may 2003 at 35,500 miles. Now it needs to be rebuilt again at 55,000 miles. All bearings and cones were replaced both times.

car image   Differential Unit problem of the 2004 Mercury Mountaineer 17
Failure Date: 04/20/2004

I purchased my 2004 Mercury Mountaineer in oct 2003. The vehicle was making a roaring noise, once taken in Ford replaced the rear differential and rear drive shaft, also complained of rough shifting of transmission around 30-35 mph changing from 2nd to 3rd gear. The solenoid was replaced, additive added, many reprograms but after 6 trips to dealer still is not corrected. 18 months later roaring noise appeared again and same rear drive shaft was replaced. The vehicle has less than 30,000 miles.

car image   Differential Unit problem of the 2002 Mercury Mountaineer 18
Failure Date: 07/11/2003

The rear differential bearings have gone bad. The complete differential was replaced in July, 2003, September 04, and in an attempt to do something different to fix the problem the drive shaft was replaced in October 2005. Now it is February 2006 and the bad bearing noise is back. We are taking it into the dealer yet again for the same problem. We are also going to notify Ford and the California consumer protection agency and bbb.

car image   Differential Unit problem of the 2002 Mercury Mountaineer 19
Failure Date: 06/18/2003

At 34,365 miles we had to replace the rear end. It was covered by warranty. Now at 58,472 miles we are having to replace it again. This time it will cost approximately $1400.

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