Master cylinder or brake booster failure on the 2010 Ford Fusion
When master cylinder or brake booster failure gets reported
Owners of the 2010 Ford Fusion report master cylinder or brake booster failure at a median of 115,000 miles. A quarter of the reports come in before 72,500 miles and a quarter after 137,500 miles, from 30 reports that carried an odometer reading.
A part like this is normally expected to survive 92,000 miles. It is the 23rd most-reported problem on this model year.
The mileage distribution
The reported range runs from 32,500 miles at the tenth percentile to 152,500 miles at the ninetieth, a spread of 120,205 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.
17% of the dated reports were filed under 36,000 miles.
The whole distribution
| 10th | 25th | Median | 75th | 90th |
|---|---|---|---|---|
| 32,295 miles | 72,000 miles | 116,000 miles | 137,750 miles | 152,500 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
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 carries the most reports, with 66; the 2010 has 42. A mode that appears across most years of a model is usually a design choice rather than a bad batch.
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.
I own a 2010 ford fusion and I have been having problems with the brake pedal going down to the floor. The brakes are soft, and the brake pedal is not operating correctly. I took it to a shop to have the brakes check to see if I needed new brake pads or what the issue was. I was referred to the dealer for possible factory warranty brake condition, stating it has tsb on brake booster switch, brake pedal level switch problem. I have taken my car to the dealer 3 times and they state there is nothing wrong with the brakes, but when driving the vehicle the brakes are not operating correctly. The brake pedal is going down to the floor when braking is not a normal operation, driving this car is dangerous. The brakes feel like a sponge and I fear one day this car is not going to stop, and I have explained this to the mechanic at the dealership as well as the manager in the service department. Well my fear almost came to light when I had to floor the brakes to stop the car while driving on the highway. I have been told by the dealership there is nothing they can do because their is no recall on the brakes and there is no service complaint…
I own a 2010 ford fusion and I have been having problems with the brake pedal going down to the floor. The brakes are soft, and the brake pedal is not operating correctly. I took it to a shop to have the brakes check to see if I needed new brake pads or what the issue was. I was referred to the dealer for possible factory warranty brake condition, stating it has tsb on brake booster switch, brake pedal level switch problem. I have taken my car to the dealer 3 times and they state there is nothing wrong with the brakes, but when driving the vehicle the brakes are not operating correctly. The brake pedal is going down to the floor when braking is not a normal operation, driving this car is dangerous. The brakes feel like a sponge and I fear one day this car is not going to stop, and I have explained this to the mechanic at the dealership as well as the manager in the service department. Well my fear almost came to light when I had to floor the brakes to stop the car while driving on the highway. I have been told by the dealership there is nothing they can do because their is no recall on the brakes and there is no service complaint…
The brakes on my 2010 ford fusion go to the floor and I need to pump them continuously to get my car to stop. When it first happened I took it to a shop and they said it did not have brake fluid. I had my brakes flushed and brake fluid added. The brakes were good for about two weeks and then they again went to the floor. I took them into a brake shop and they did a reverse bleed, checked my pads, my ABS system, my master cylinder, flushed them again and did not find any leaks or any problems. My brakes worked for about two days and then it happened again. Now it is a daily occurrence and I do not know what to do other than replace the m/c which I have been told is not bad. No leaking behind it or around it. I am at a loss. Something is wrong with my brakes and I have read that other 2010 ford fusion owners have had this problem. *tr
Also reported on the 2010 Ford Fusion
Other steering problem
Other powertrain problem
Other speed control problem
Other engine problem
Other fuel system problem
Airbag inflator rupture
How far this goes
Complaints are voluntary, so 42 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 2010 Ford Fusion?
Across 30 owner reports that included an odometer reading, half were filed by 115,000 miles. A quarter were filed before 72,500 miles and a quarter after 137,500 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 2010 Ford Fusion?
42 reports have been filed with NHTSA, about 0.4 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