Master cylinder or brake booster failure on the 2004 Chevrolet Silverado 2500
When master cylinder or brake booster failure gets reported
Owners of the 2004 Chevrolet Silverado 2500 report master cylinder or brake booster failure at a median of 100,000 miles. A quarter of the reports come in before 55,000 miles and a quarter after 105,000 miles, from 9 reports that carried an odometer reading.
A part like this is normally expected to survive 92,000 miles. It is the 13th most-reported problem on this model year.
The mileage distribution
The reported range runs from 45,000 miles at the tenth percentile to 125,000 miles at the ninetieth, a spread of 79,784 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.
11% of the dated reports were filed under 36,000 miles.
The whole distribution
| 10th | 25th | Median | 75th | 90th |
|---|---|---|---|---|
| 45,816 miles | 56,658 miles | 100,000 miles | 107,138 miles | 125,600 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 6 model years of this car. It shows up earliest on the 2005, at a median of 40,000 miles, and latest on the 2004 at 100,000 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.
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.
Tl*the contact owns a 2004 chevrolet silverado 2500 hd. While driving 60 MPH, the brake pedal extended to the floor when depressed. As of september 10, 2007, the dealer had not inspected the vehicle. The failure and current mileages were 24,194. *updated 12/12/2007 *bf the consumer stated replaced the master cylinder fix problem. Updated 12/12/07 *tr
Tl*the contact owns a 2004 chevrolet silverado 2500 hd. The contact stated that he experienced increased stopping distance when braking at any speed. The vehicle was taken to an authorized dealer where the contact was informed that the vehicle was leaking brake fluid. The vehicle was repaired at that time. The failure occurred three times after the repair and the vehicle was taken back to the dealer. While driving approximately 25 MPH, the contact applied pressure to the brake pedal which extended to the floorboard. He applied the emergency brake and the vehicle rolled to a stop. The vehicle was towed to an authorized dealer where the contact was informed that the brake lines were corroded. The vehicle was repaired. The failure had not occurred since the repair. The failure mileage was 51,222 and the current mileage was approximately 83,000. Updated 12/29/10 *bf also, the hydro brake booster was leaking. Updated 04/06/11
Truck: 2004 chevrolet silverado 2500hd, 6.6l diesel. Location: upstate ny problem: while testing the brakes before towing a trailer, the pedal pushed completely to the floor and brake fluid poured to the ground from under the drivers side door. Upon inspection of the brake lines, it showed one of the lines on the frame rail had severe corrosion and had burst. All of the brake fluid drained out of the master cylinder through this broken line. I checked the operation of the brakes after the broken line to see if I had any ability to stop the vehicle. This was not the case as the brakes would not even stop the vehicle from moving at an idle. If this had occurred at operating speeds, especially while towing, I would have not been able to stop the vehicle. Currently the truck is at a repair facility to have the lines replaced and system checked. *tr
Also reported on the 2004 Chevrolet Silverado 2500
Instrument cluster or gauge failure
Loss of braking
Other brake problem
Brake line, hose or caliper failure
Other electrical problem
Exhaust leak or fumes in the cabin
How far this goes
Complaints are voluntary, so 9 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 Chevrolet Silverado 2500?
Across 9 owner reports that included an odometer reading, half were filed by 100,000 miles. A quarter were filed before 55,000 miles and a quarter after 105,000 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 2004 Chevrolet Silverado 2500?
9 reports have been filed with NHTSA, about 31 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