Master cylinder or brake booster failure on the 2006 Toyota Highlander
Only 4 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.
When master cylinder or brake booster failure gets reported
There are 6 reports of master cylinder or brake booster failure on the 2006 Toyota Highlander, 4 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 14th most-reported problem on this model year.
The whole distribution
| 10th | 25th | Median | 75th | 90th |
|---|---|---|---|---|
| — | — | 90,863 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 9 model years of this car. It shows up earliest on the 2023, at a median of 10,000 miles, and latest on the 2010 at 165,000 miles.
By volume the 2008 carries the most reports, with 20; the 2006 has 6. 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.
Tl* the contact owns a 2006 toyota highlander. The contact stated that there was no hydraulic pressure on the brake pedal and the pedal traveled too far into the floorboard when depressed. The contact believed that there was either air in the braking system or a defective master cylinder. The problem was intermittent. The vehicle was taken to an authorized dealer where the brakes were bled twice but the failure continued. The contact called the manufacturer who advised him to take the vehicle to the dealer but offered no further assistance. The vehicle was not repaired. The failure mileage was approximately 150 and the current mileage was approximately 35,000.
Tl* the contact owns a 2006 toyota highlander. The contact stated the brake pedal extended to the floor when the brakes were applied and the braking distance had increased. The contact took the vehicle to a local mechanic who replaced the master cylinder. The contact stated after the vehicle was repaired the brakes did not feel safe and the vehicle was driven to the dealer. The dealer stated the front brake pads were replaced; however, the contact did not have the front brake pads replaced. The contact stated the master cylinder was still faulty and the vehicle was unsafe to drive. The VIN was not available. The failure mileage was 105,000.
The vehicle failed to stop when depressing the brake pedal. The pedal suddenly felt 'soft' and the vehicle continued to move. After stomping on the brake again the vehicles' braking system engaged with a jerk and began working normally again. This happened several times over a period of a few days before taking the vehicle into a toyota dealership for repair. Dealership identified a faulty master cylinder and booster assembly - both of which are covered under a limited recall on 2004 - 2006 highlanders. Unfortunately not all 2006 highlanders are covered even though they experience the exact same malfunction. *tr
Also reported on the 2006 Toyota Highlander
Other brake problem
Other speed control problem
Other engine problem
Other electrical problem
Other visibility problem
ABS module or sensor failure
How far this goes
This page is kept out of search results because 6 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 6 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 2006 Toyota Highlander?
Across 4 owner reports that included an odometer reading, half were filed by 90,000 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 2006 Toyota Highlander?
6 reports have been filed with NHTSA, about 0.1 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