Which parts fail
Components named in complaints (service brakes, ABS, rotors and pads, parking brake).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2008 Mercury Mariner owners, lightly cleaned up (personal details are redacted by NHTSA).
The contact owns a 2008 Mercury Mariner. The contact stated that while driving at 30 MPH, he had to hard brake, however, afterward while depressing the brake pedal, the brake pedal traveled to the floorboard. The vehicle was taken to the dealer where the failure was diagnosed as a hydraulic control unit (HCU) failure. The contact was informed that the HCU needed to be replaced. The contact stated that the vehicle was not repaired as the parts were on backorder. The contact stated that he discovered NHTSA Campaign Number: 19V904000 (Service Brakes, Hydraulic) however, the VIN nor the Year/Make/Model was not included in the recall. The manufacturer was notified of the failure and informed that contact to call the NHTSA Hotline to file a complaint. The approximate failure mileage was 89,000.
Brakes go to floor dealer said they see nothing. They gave my vehicle back brake are normal again.two months go by it happens again but it fixed itself after 2 days. This just happen again 8/5/2022. I see a recall NHTSA campaign #19V904000 ,MFG campaign #19S54 Also a NHTSA recall#150546 How am I going to drive with brakes on the floor My vehicle is a 2008 Mercury Mariner Thanks in advance
I lost all braking ability and the pedal goes to the floor. This is a Mercury Mariner Hybrid and Ford Escape Hybrid issue, it doesn't affect the non-hybrid models. Ford knows about this as there are hundreds and hundreds of complaints online about it and it's a $5000+ fix. I have not been able to drive my Mariner Hybrid since 2018.
Takata recall my ABS light and brake light comes on and if I drive it with these lights on I smell my break pads burning. I took it to Ford and they said it was the internal failure of the hydraulic control unit and it would cost me upwards of $5,885.00 to replace and repair the problem. I have searching the internet and there are several other people with the same problem with this vehicle and Ford escapes. (which is basically the same vehicle. If there are this many complaints maybe its worth looking into on dots part. It is a safety issue for sure considering my brakes go to the floor when the ABS and brake lights are on. I can turn my SUV off and remove the key and then put the key back in and start it again until the lights go off and I don't have an issue. But when I first get in the vehicle and start it the lights do in fact come on. …
My 17 year old daughter came home saying a message was on her dash about her brakes in our 2008 Mercury Mariner hybrid. I was about to leave so I decided to take her car, as soon as I pulled out of the driveway and started down the hill we live on, I noticed the brakes didn't feel right, I pressed all the way down to get the car to slowly come to a stop, as I did this, I noticed a warning sound and the message on the screen said check brake system, regen brakes disabled. I immediately turned the car around and went home, when trying to stop in our driveway, again the brakes were not working properly causing us to almost hit the other car in the driveway. This is extremely concerning as this car is our 17 year old daughters car. Once you get the car to stop, if the car is powered off for a few minutes and back on the brakes work again. …
The brake light came on and indicated "regen brakes disabled". I braked when I came to a traffic light and ended up skidding into the middle of an intersection. The local Ford dealer advised to replace the hcu for $5000. The unit has 55K miles on it. This has continued to happen for the last 2 years, mostly in the summer when it is hot and humid, although just today it happened again (it was 35 degrees all day). I couldn't stop in time and ran off the road onto the median. Some online research has indicated the problem is not with the hcu, but the sensors (replacing the hcu reestablishes a good connection with the sensors)., but the Ford dealer knows nothing about this fix because it's much cheaper. So, I have no choice but to continue to drive this train wreck and hope I'm not in a serious accident.
Re:NHTSA identifier 19V904 Ford internal reference number:19s54 although Mercury mariners are not listed in this recall, my 2008 Mercury Mariner has the exact same issue, sticking ABS valve. Ford will not recognize my vehicle as part of this recall. I have had 2 different certified mechanics work on the vehicle and both mechanics have installed new brake boosters, brake pads and master cylinders. The results from their work did not resolve the issue of soft brakes. The problem began when I made an abrupt stop while driving on a city street. The brakes were never fully functional after that. I believe the situation with my Mariner is identical to the issue identified in the NHTSA identifier 19V904. I also believe that Mercury mariners should be included in this Ford recall.
Tl* the contact owns a 2008 Mercury Mariner. The contact stated that while driving at 25 MPH, the brake pedal was depressed but failed to stop the vehicle. The contact stated that the brake pedal required excessive pressure to slow the vehicle. The vehicle was taken to an independent mechanic to be diagnosed. The contact was informed that the brakes master cylinder needed to be replaced. The vehicle was repaired however, the failure recurred. The contact also stated that the brake pads were also replaced however, the failure recurred. The contact stated that the failure occurred only when driving while it was raining. The manufacturer was not notified of the failure. The approximate failure mileage was 120,000.
I started having problems with my brakes. When I step on the brake the pedal would go almost all the way to the floor. I would react by pumping the brake which would make them work. I didn't drive with the brakes doing that very long because I took the car to a repair shop and I spent 450 dollars on brake work with being told that the problem was with the ABS system and the disabled the ABS system so that it didn't interfere with stopping the car. There have been recalls on other Ford products because of ABS problems. The problem occurred while I was driving every time I wanted to stop and when I stopped for a light I felt like the brakes might quit working and the car could enter the intersection.
Tl* the contact owns a 2008 Mercury Mariner. The contact stated on several occasions while the vehicle was idle or being driven, the steering wheel vibrated abnormally. The contact also stated that when the steering wheel was turned there was there was a hesitation in response to the wheels responding. Additionally, the contact stated that there was a clicking sound in the steering. The contact stated that the clicking sound emitted from the intermittent shaft. The vehicle was taken to an independent mechanic who replaced the brake pads, brake rotors, and provided an alignment. Neither the dealer nor the manufacturer was contacted or informed of the failure. The failure mileage was 103,184.
Brake complaints in other Mariner years
Frequently asked questions
How common are brake problems on the 2008 Mercury Mariner?
NHTSA has 35 complaints about the brakes of the 2008 Mercury Mariner, 8% of the model year's 461 complaints. The component named most often is foundation components › master cylinder (1 mentions).
Is there a recall for 2008 Mercury Mariner brake problems?
No. NHTSA lists no brakes recall for the 2008 Mercury Mariner, though it has 3 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2008 Mercury Mariner brake problems start?
Half of the complaints with a recorded mileage happened before about 102,000 miles, and 10% before 25,000 miles.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.