PULSCAR ANALYSIS — THE BRAKE MASTER CYLINDER IN NHTSA'S PUBLIC FILES
PulsCar analysis of NHTSA public data, September 2026.
License: CC BY 4.0. Attribution: "PulsCar analysis of NHTSA public data, September 2026."
Published alongside https://www.pulscar.io/blog/master-cylinder-replacement-cost

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1. SOURCE FILES
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NHTSA's published flat files loaded into SQLite without modification:
complaints (777,040 received 1 Jan 2015 - 8 Sep 2026), recalls (reported
1 Jan 2010 - 9 Sep 2026), manufacturer communications, investigations.
Downloaded from static.nhtsa.gov and read in full on 23 September 2026:
Toyota customer support programs ZJB dealer letter (10158577), 21TE01
(10198141), 24TE05 (11014218). Recall records and investigation closing
reports read in NHTSA's published text the same day.

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2. THE COMPLAINT SET
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FTS5 candidates for "master cylinder"; kept if the narrative contains
"brake master", or contains "master cylinder" without "clutch master":
3,096 complaints. master-cylinder-complaints-by-model.csv,
master-cylinder-complaint-set-summary.csv.
   Ford 1,388 + Mercury 64 + Lincoln 56 = 1,508 (48.7%); Toyota 365;
   Chevrolet 254; Nissan 154.
   Top models: F-150 655 (2013-2016: 552), Fusion 246, Edge 231, Prius 161,
   Expedition 82, Murano 76, Escape 66, Silverado 1500 60, Tacoma 56.
   Flags: crash 125 (4.04%; all complaints 4.37%), injuries 47, fire 36,
   towed 168. Pattern counts: pedal sank / to the floor / soft 1,213;
   booster 1,161; recall 1,034.
   2023-and-newer GM models: 103 complaints (2025 Traverse 42, 2025 Acadia
   15, Colorado 11); 25 mention back order or no availability; received
   mostly July 2025 onwards.
   Mileage reported in 2,051: median 75,000; quartiles 42,000 / 75,000 /
   116,000; at or under 36,000: 425. Medians: F-150 50,409; Fusion 106,213;
   Prius family 119,955.
30 random complaints (random.seed(2026)) read in full
(master-cylinder-30-complaints-read.csv): 17 master cylinder diagnosed or
replaced as the cause; 7 master cylinder replaced without curing the
problem (in 5 the next suspect was the ABS hydraulic unit); 6 other parts
or incidental mentions (including a clutch master cylinder).

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3. OWNER-REPORTED AMOUNTS (master-cylinder-owner-reported-amounts.csv)
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Every sentence containing both "master cylinder" and a dollar figure: 137,
each read by hand. 98 figures published in lanes:
   master cylinder alone, paid      20   $290.23-$1,703.22   median $559.52
   master cylinder alone, quoted    11   $500-$3,000         median $1,500
   master cylinder + booster        25   $459-$2,500         median $1,032
   master cylinder + ABS unit        7   $1,400-$3,700       median $3,000
   hybrid / integrated assemblies   34   $1,516.89-$9,000    median $3,969.44
      of which Toyota Prius family  26   $1,516.89-$5,800    median $3,600
   part bought by an owner           1   about $80
Not invoices; complaints over-represent bad outcomes.

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4. DOCUMENTS (master-cylinder-recalls-programs-investigations.csv)
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30 recalls, programs, petitions and investigations with dates, vehicle
counts and status in September 2026.

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5. WHAT THIS IS NOT
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Complaint counts are not failure rates. Prices marked as estimates in the
article are carried from PulsCar repair guides and were not re-checked in
this pass.