Master cylinder or brake booster failure on the 2008 Ford Fusion
2 crashes 2 of the 66 reports for this failure mention a crash, a fire, an injury or a death. Those are the owner's words on the complaint form, not a verified finding, and one report can mention more than one.
When master cylinder or brake booster failure gets reported
Owners of the 2008 Ford Fusion report master cylinder or brake booster failure at a median of 97,500 miles. A quarter of the reports come in before 72,500 miles and a quarter after 132,500 miles, from 62 reports that carried an odometer reading.
A part like this is normally expected to survive 92,000 miles. It is the 5th most-reported problem on this model year.
The mileage distribution
The reported range runs from 37,500 miles at the tenth percentile to 180,000 miles at the ninetieth, a spread of 142,086 miles across the middle 80% of reports.
A spread this wide points at use rather than design. Towing, climate, service history and city mileage all move a failure like this, so the median is a weak guide to any individual car.
8% of the dated reports were filed under 36,000 miles.
The whole distribution
| 10th | 25th | Median | 75th | 90th |
|---|---|---|---|---|
| 36,900 miles | 72,150 miles | 97,000 miles | 132,000 miles | 178,986 miles |
Read the 10th percentile as “one report in ten arrived this early”. Exact figures are shown in this table because it is the table of record; everywhere else on the site they are rounded to the precision the sample can carry.
What a percentile can and cannot tell you here
These five numbers describe the readings owners gave, in order. The median is the middle one: half the reports arrived below it. The 10th and 90th are the edges of the bulk of the distribution, and the distance between them is the part worth reading. A tight spread — say 70,000 to 95,000 miles — points at something that wears out on a schedule, and the schedule is knowable. A wide one, 20,000 to 190,000, points at a fault that hits some cars and never troubles others, which means the mileage on the listing in front of you tells you very little about your odds.
What these figures are not is a survival curve. Every reading here comes from a car whose owner filed a complaint, so the sample contains only failures: it cannot say what share of the fleet made it past 150,000 miles untouched, because those owners had nothing to report. Nor is the mileage the moment of failure — it is the odometer reading as recalled at the time of filing, which may be weeks later and is sometimes rounded to the nearest ten thousand by the person typing it.
Percentiles are shown at all only once 8 readings exist for the vehicle and mode. Below that the middle of a handful of numbers is noise wearing a decimal point, so the figures are withheld rather than dressed up.
What happens, and what it costs
Of these reports, 2 a crash is mentioned. Owners write their own complaints and the agency does not verify them, so read this as what the reports say happened rather than as a confirmed count.
Putting it right typically runs $450–$2,200 at an independent US shop. That range is an editorial estimate held in this site's failure-mode catalogue, not a figure from NHTSA, and it is a repair cost rather than a diagnosis cost.
This mode is classified as critical, which means a failure can leave the car unable to stop, steer, or stay out of the way of traffic. It is weighted accordingly in the risk score.
The same failure on other years
The same failure is reported on 10 model years of this car. It shows up earliest on the 2012, at a median of 95,000 miles, and latest on the 2016 at 200,000 miles.
By volume the 2008 is the worst of them, which makes this a problem of this specific year rather than of the model as a whole.
If one year stands out to the left, that is the year to avoid; if the whole line sits at a similar mileage, this is wear rather than a defect in one production run.
Tick median reported mileage Solid middle half of reports Faint 10th to 90th percentile Colour how bad the failure is when it happens
What owners wrote
Verbatim from NHTSA complaint narratives, trimmed for length. The mileage is the one the owner gave.
Was driving and as I went around a corner, the brake pedal (which was slightly depressed) went completely to the floor. Lost all pressure. I pulled into a parking lot. Turned car off and back on. Gradually pressure resumed. Drove another day or so and it happened again while I was going straight. I went to the dealer. Had my master cylinder, brakes, rotors, and brake booster all replaced. That was the beginning of september. Now in december, it is happening again. *tr
Its the ABS. I have changed the brakes gotten new master cylinder and I still cannot get full brake control. Still pushing pedal almost to the floor. My mechanic checked on this site which showed others with same problem. Which he stated is a factory defect. *tr
While driving the vehicle and needing to come to a stop the brake pedal is soft and goes striaght to the floor. We have had the brakes checked and all the fluid and those are fine. I have been told that it could be the master cylinder but probably the hydraulic cylinder unit. The dash by the passanger air bag is lifting from the dashboard. I have seen many of the same exact post for both issues. A recall needs to be made on these parts before someone seriously gets hurt. This is unexceptable that ford is not taking car of these issues. There is obviously a serious problem with as many people that are reporting the same exact issues that my car is experiencing. Take this serious please, submit through recalls so people don't have to die or get seriously hurt in an accident to get your attention. *tr
Also reported on the 2008 Ford Fusion
Airbag inflator rupture
Other brake problem
Other body or interior problem
Loss of braking
ABS module or sensor failure
Control module (ECM/PCM/BCM) failure
How far this goes
Complaints are voluntary, so 66 is a floor and not a count of affected cars. Mileages are typed in by owners and cluster on round numbers. And the mode itself is assigned by software reading the complaint text, which is reliable in bulk and fallible one report at a time.
Questions this page answers
At what mileage does master cylinder or brake booster failure happen on the 2008 Ford Fusion?
Across 62 owner reports that included an odometer reading, half were filed by 97,500 miles. A quarter were filed before 72,500 miles and a quarter after 132,500 miles. These are the mileages owners reported when they complained, not a prediction for any individual car.
How common is master cylinder or brake booster failure on the 2008 Ford Fusion?
66 reports have been filed with NHTSA, about 1.0 per 1,000 vehicles. Complaints are voluntary, so this is a floor rather than a count of affected cars.
What this is and is not. These are the mileages at which owners chose to complain to a federal agency, which is not the same as the mileage at which the part fails on every car. It skews toward failures that happened outside warranty, cost real money, or frightened someone. It is still the only public dataset that carries failure mileage at all, and the shape of a few hundred readings is informative even when a single one is not. Methodology · JSON · this failure on other cars
Source Owner complaints and recall records published by the US National Highway Traffic Safety Administration, model years 1996–2027 Figures rebuilt Published by AtWhatMileage How every figure is computed