AtWhatMileage
Brakes · 5 owner reports

Master cylinder or brake booster failure on the 2004 Honda Pilot

3 crashes 3 injuries 6 of the 5 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.

Only 5 reports for this mode came with an odometer reading, which is too few for percentiles to mean anything. The page is here because someone linked to it; treat the figures as anecdotes, and see the full report for this year instead.

Reports of this failure 5
With an odometer reading 5
Reports per 1,000 built 0.0 per 1,000
Filed below 36,000 miles 20%
Mention a crash, fire or injury 6
Typical repair $450–$2,200
What it means when it happens Critical
Rank among this year's problems 23rd

When master cylinder or brake booster failure gets reported

There are 5 reports of master cylinder or brake booster failure on the 2004 Honda Pilot, 5 with a mileage attached. That is too few to place the failure on the odometer with any confidence.

A part like this is normally expected to survive 92,000 miles. It is the 23rd most-reported problem on this model year.

The whole distribution

Percentiles of the 5 odometer readings owners gave.
10th25thMedian 75th90th
— — 135,000 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, 3 a crash and 3 an injury are 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 3 model years of this car. It shows up earliest on the 2003, at a median of 15,000 miles, and latest on the 2004 at 135,000 miles.

By volume the 2004 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.

What owners wrote

Verbatim from NHTSA complaint narratives, trimmed for length. The mileage is the one the owner gave.

Tl* the contact owns a 2004 honda pilot. While driving at speeds of 35 MPH and applying the brakes to approach a traffic stop, the brakes did not engage. The contact immediately shifted into a lower gear as the vehicle proceeded through the traffic stop, barely avoiding a crash. The dealer performed a diagnostic and found the master cylinder had failed. The master cylinder was replaced by the dealer however; the contact stated the repair did not address the failure. The dealer was unable to locate the exact cause of the failure. The VIN was not available. The failure and current mileages were 29000.

29,000 miles NHTSA complaint 782705 filed 2010-04-20

04 honda pilot master cylinder slow leak causing brake warning light to show on instrument panel. Have only used honda fluid. Have seen that honda is recalling 05 to 07 odyssey and acura rl vehicles for this problem. 04 pilot should be included. *tr

40,000 miles NHTSA complaint 830237 filed 2010-12-11

I was parked in the driveway on a completely flat surface. I put the car in reverse to back out of the driveway. I touched the accelerator pedal lightly to get the car moving, the car accelerated wildly. I stomped on the brake, which went to the floor. I had time to look down and see that my foot was on the brake pedal and to stomp on the emergency brake. The car did not slow down at all. The vehicle continued accelerating until it smashed into a tree going approximately 30 MPH (estimated). A couple hours before the wreck a previously unseen brake error light came on the dash. The shop it was taken to refused to look into the brakes, accelerator, master cylinder or the transmission. They stated there were no codes triggered, though they could provide no proof that they even had the necessary equipment to read the codes. State farm insurance refuses to investigate because the vehicle was a total loss. This from a stand still on a flat surface. It was horrific. I would like the vehicle inspected to determine if there was a mechanical failure. *tr

135,000 miles NHTSA complaint 934629 filed 2012-08-17

Also reported on the 2004 Honda Pilot

Other body or interior problem

115 reports median 110k

Other powertrain problem

83 reports median 106k

Other electrical problem

39 reports median 106k

Other engine problem

38 reports median 89k

Torque converter failure

34 reports median 99k

Seat belt or retractor failure

21 reports median 146k

How far this goes

This page is kept out of search results because 5 reports is not enough to publish percentiles from. It stays reachable because somebody looking at this exact car would rather see the reports than be told there are none.

Complaints are voluntary, so 5 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 2004 Honda Pilot?

Across 5 owner reports that included an odometer reading, half were filed by 135,000 miles. A quarter were filed before — and a quarter after —. 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 2004 Honda Pilot?

5 reports have been filed with NHTSA, about 0.0 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