There are 50 owner-reported powertrain & transmission complaints for the 2004 Mercury Mountaineerin NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
This vehicle is has a power train problem from day one with the 5R55S/W transmission and AWD transfer case. I purchased this vehicle where it stranded my family over 200 miles from home and it's a non running car. This vehicle should have been removed from being sold with this defect and crushed! I will never buy a FoundOnRoad Dead ford pos ever. The transmission went into neutral with out any notice. To repair the faulty drive train I will cost me aprox $2400.00 mileage 152,000 third time the drive train has been worked on.. There tranmissions were failing in a little as 50,000 miles.
TL* THE CONTACT OWNS A 2006 MERCURY MOUNTAINEER. THE CONTACT STATED THAT WHILE DRIVING 70 MPH, THE VEHICLE LOST POWER WITHOUT WARNING. THE VEHICLE WAS MERGED TO THE SIDE OF THE ROAD WHERE IT WAS RESTARTED. HOWEVER, THE VEHICLE FAILED TO ACCELERATE PAST 35 MPH. THE VEHICLE WAS TAKEN TO AN INDEPENDENT MECHANIC WHERE THE TECHNICIAN DIAGNOSED THAT THE POWER TRAIN NEEDED TO BE REPLACED. THE MANUFACTURER WAS MADE AWARE OF THE ISSUE. THE FAILURE MILEAGE WAS 99,000. THE VIN WAS NOT AVAILABLE.
COLUMN MOUNTED GEARSHIFT SELECTOR BROKE OFF WHEN MOVING IT FROM DRIVE TO PARK. *TR
THE TRANSMISSION IS SLIPPING BETWEEN GEARS, REVVING WAY HIGHER THAN NORMAL TO SHIFT AND WON'T GO INTO OVERDRIVE. MY RESEARCH OF THE PROBLEM SHOWS THIS IS A COMMON ISSUE ON FORD AND MERCURY VEHICLES IN THIS YEAR RANGE. *TR
FAILURE OF FRONT DIFFERENTIAL MOUNT CARRIER BUSHINGS FAILURE LEADING TO TWO TRANSMISSION REBUILTS,TRANSFER CASE REBUILD, AND OVER $5000.00 IN REPAIRS. FAILURE OF CARRIER BUSHINGS WOULD LEAD TO FRONT END LOCKING UP. CAUSING A JACKHAMMER AFFECT ON THE DRIVETRAIN OF THE VEHICLE. TO CLOSE CALLS DUE TO FRONT END LOCKING UP. ACCIDENTS WERE AVOIDED DUE TO DRIVER VIGILANCE. HAVE PICTURES OF BUSHINGS AND WHAT'S LEFT OF THE BUSHINGS.
2004 MERCURY MOUNTAINEER WHOLE TRANSMISSION IS BAD FROM REVIEWS AND BLOGS FROM ALOT OF PEOPLE RECENTLY READ AND READ CONSTANT BLOGS ABOUT THE SAME TRANSMISSION PROBLEMS THAT. I'M HAVING ITS FOR SURE A DEFECT FROM MERCURY IM PUTTING RISK ON MY FAMILY WITH THIS VEHICLE CONSULT IT WITH A MECHANIC AND SAID MERCURY MOUNTAINEER EXPLORERS AND AVIATOR ALL HAD TRANSMISSION PROBLEMS THERE NEEDS TO BE SOMETHING DONE ABOUT THIS I REALLY DON'T HAVE THE MONEY TO PURCHASE A NEW VEHICLE. *TR
TRANSMISSION SEEMS TO BE FAILING OR TRANSFER CASE ITS REALLY A BIG PROBLEM BECAUSE WHEN I DRIVE ONTO THE EXPRESS WAY A RATTLING NOISE GETS LOUDER AS I ACCELERATE I FEEL CONCERNED ABOUT MY SAFETY AND MY CHILDREN PLUS OTHER DRIVERS THEY SHOULD RECALL FOR VEHICLE INSPECTION I AM VERY UPSET AND SCARED. *TR
I PURCHASED A 2004 MERCURY MOUNTAINEER FIRST THE REAR LIFTGATE PLASTIC BROKE AND THERE'S A CRACK BY THE EMBLEM ON SOME OCCASIONS WHEN PUT IN REVERSE IT MAKES A LOUD BANG NOISE OR WHEN STARTING TO ACCELERATE BUT THE BIGGEST PROBLEM IS THAT ON THE HIGHWAY UP TO 50MPH AND OVER THERE SEEMS TO BE A RATTLE UNDER THE ENGINE AND IT GETS LOUDER WHEN MPH IS HIGHER IM NOT SURE WHAT IT IS BUT IM REALLY WORRIED THAT IT MAYBE A TRANSMISSION PROBLEM AND IF THIS PROBLEM ISN'T RECALLED ME AND MY FAMILY PLUS OTHERS ARE IN REALLY BIG DANGER ITS A FAMILY CAR SO IM STARTING TO WORRY FOR MY FAMILY AND THERE SAFETY THESE VEHICLES NEED TO GO ON INSPECTION AND SOON SO THESE DOESN'T LEAD TO ANY ACCIDENTS. *TR
TL* THE CONTACT OWNS A 2004 MERCURY MOUNTAINEER. THE CONTACT STATED THAT THE SHIFTER WOULD NOT SHIFT INTO PARK DUE TO A DEFECTIVE SHIFT CABLE. THE CONTACT TOOK THE VEHICLE TO A LOCAL MECHANIC WHERE THE MECHANIC ADVISED THAT THE SHIFTER CABLE NEEDED TO BE REPLACED. THE CONTACT DID NOT HAVE THE SHIFTER CABLE REPLACED. THE FAILURE MILEAGE WAS 140,000.
TRANSMISSION SOLENOIDS THREE TIMES, PAINT COMING OFF, PASSENGER SEAT TRIM CAME OFF, CRACKED REAR LIFT GATE, PASSENGER FRONT AND REAR DOOR WINDOWS, AND DRIVER SIDE REAR DOOR WINDOW DO NOT WORK. *TR
TL* 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.
TRANSMISSION FAILED AT 58,000 AND WAS REBUILT ( NOT REPLACED) UNDER WARRANTY. NOW LESS THAN 24,000 MILES AND 27 MONTHS LATER AT 84,000 MILES, TRANSMISSION HAS FAILED AGAIN. THE REBUILT TRANSMISSION HAS NOT EVEN HIT THE 30,000 MILES MAJOR TRANSMISSION SERVICE TIME. *TR
THE TRANSMISSION FAILED ON MY 2004 MOUNTAINEER THE FIRST TIME IN JULY 2009 WITH ONLY APPROX 58,000 MILES. IT WAS UNDER WARRANTY. I WAS TOLD BY THE MERCURY DEALERSHIP THAT MY TRANSMISSION WOULD HAVE TO BE REBUILT FOR THE TRANSMISSION WAS ON NATIONAL BACK ORDER FOR A BRAND NEW TRANSMISSION. I MADE AN INQUIRY AS TO WHY A TRANSMISSION WOULD BE ON NATIONAL BACK ORDER??. NOW AT APPROX 84,000 MILES THE WARRANTY REBUILT TRANSMISSION HAS FAILED AGAIN . THAT IS ONLY 24,000 MILES PUT ON THE REBUILT TRANSMISSION. MY REBUILT TRANSMISSION HAS NOT EVEN HIT THE 30,000 MILES MAJOR TRANSMISSION SERVICE TIME. MY WARRANTY EXPIRED AT 75,0000 MILES . MY DEALERSHIP HAS INFORMED ME I HAVE NO WARRANTY ON A TRANSMISSION THAT WAS REBUILT UNDER WARRANTY PAST 75,0000 MILES. *TR
TL* THE CONTACT OWNS A 2004 MERCURY MOUNTAINEER. THE CONTACT STATED THAT THE VEHICLE WAS PARKED, WITH THE REAR LIFT GATE OPENED, WHEN IT BEGAN TO ROLL BACKWARDS. WHILE ATTEMPTING TO ENTER THE MOVING VEHICLE, THE CONTACT WAS KNOCKED DOWN AND SUSTAINED INJURIES. THE VEHICLE CONTINUED TO ROLL BACKWARDS UNTIL CRASHING INTO A TREE. THE VEHICLE WAS NOT TAKEN TO HAVE THE FAILURE DIAGNOSED OR REPAIRED. THERE WAS AN INVESTIGATION OPEN UNDER NHTSA ACTION NUMBER: EA09013 (STEERING POWER TRAIN:AUTOMATIC TRANSMISSION:GEAR POSITION INDICATION (PRNDL) STEERING:COLUMN STEERING:COLUMN LOCKING:ANTI-THEFT DEVICE) THAT MAY BE RELATED TO THE FAILURE. THE FAILURE MILEAGE WAS 82,000. THE VIN WAS UNAVAILABLE.
AUTOMATIC TRANSMISSION SHIFTER COMPLETELY BROKE OFF WHEN CHANGING FROM PARK TO DRIVE ON A 2004 MERCURY MOUNTAINEER. *TR
REAR DOOR PANEL CRACKED, VISUAL, THEN FOUND SEVERAL MORE 2004 MOUNTAINEERS WITH THE SAME CRACK, NOW A LAWSUIT HAS BEEN FILED AS CLASS ACTION, I HEAR A NOISE MECHANICAL GRIND FROM REAR OF VEHICLE, STOP BY A FORD DEALER TO GET A TRADE IN PRICE, AND SEE IF ANYTHING IS MENTIONED, THEY TELL ME TO GET MY CAR FIXED, !! NO MENTION THEY KNEW OF THE PROBLEMS, NOW I READ TRANSMISSION PROBLEMS, GLASS VISIBILITY PROBLEMS, CRUISE CONTROL FIRE, PROBLEMS MY CAR'S CRUISE QUIT WORKING, ON AND ON IT GOES, LISTS OF LISTS OF PROBLEMS, I KNOW CARS WEAR OUT BUT TO KNOW THERE ARE PROBLEMS AND HIDE THEM, NEEDS ACTION. *TR
HAVE A LITTLE OVER 67,000 MILES ON VEHICLE. DRIVING AT HIGHWAY SPEED TRANSMISSION INDICATOR CAME ON, O/D INDICATOR FLASHES AND SERVICE ENGINE INDICATOR CAME ON. TRANSMISSION SHIFTS ROUGHLY FROM 1ST GEAR TO 2ND, AND DOES NOT HAVE OVERDRIVE. SERVICE STATION RAN DIAGNOSTIC WHICH RESULTED IN 4 SERVICE CODES: PO732, PO735, PO775, AND PO1744. THESE CODES WERE ALSO CONFIRMED BY AAMCO TRANSMISSION. THE RESULT APPEARS TO BE TRANSMISSION SOLENOID PACK, ALONG WITH REBUILD OF THE TRANSMISSION. *TR
2004 MERCURY MOUNTAINEER V8, 47,000 MILES. TRANSMISSION IS SHOT. IT SLIPPED IN AND OUT OR REVERSE (CREATING A VERY DANGEROUS SITUATION SINCE I COULD NOT CONTROL THE VEHICLE WHEN IT WAS IN REVERSE) AND IT STRUGGLED TO SHIFT GEARS IN DRIVE. NO WARNING LIGHT BEFORE THE PROBLEMS BEGAN. THE VEHICLE AGED OUT OF WARRANTY IN JULY 2010. FORD WILL NOT PAY FOR ANYTHING (ALTHOUGH THE DEALER IS CUTTING ME A BREAK ON THE SERVICE COSTS). *TR
TL*THE CONTACT OWNS A 2004 MERCURY MOUNTAINEER. THE CONTACT NOTICED THAT WHEN DRIVING, THE TRANSMISSION WAS UNABLE TO BE SHIFTED INTO SECOND OR FIFTH GEAR. THE VEHICLE WAS TAKEN TO AN AUTHORIZED DEALER WHO INFORMED THE CONTACT THAT THE TRANSMISSION NEEDED TO BE REPLACED. THE CONTACT CALLED THE MANUFACTURER WHO TOOK A COMPLAINT BUT OFFERED NO FURTHER ASSISTANCE. THE FAILURE MILEAGE WAS APPROXIMATELY 131,000.
2004 MERCURY MOUNTAINEER. TRANSMISSION FAILING 69,469 MILES ON VEHICLE. TAILGATE CRACKED ALSO. NOT SURE IF WORTH REPAIRING. *TR
Showing 1–20 of 50 complaints
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
Data synced from NHTSA on Apr 26, 2026