Owners of 2017 F-150s describe brake failures ranging from early loss of function—some occurring at 4,500 miles in the first month of ownership—through failures at higher mileage. The core complaint is a brake pedal that abruptly goes to the floor with no braking force, often without warning lights or noise. Many report the pedal sinking gradually under sustained pressure, as if hydraulic pressure is bleeding off.
Master cylinder failure appears frequently: dealers diagnose failed internal seals, internal leaks, and fluid loss. Several owners report the master cylinder replacement alone did not resolve the problem; they were then told a hydraulic control unit or ABS module also needed replacement, extending repair time and cost. Brake booster failures are cited, with DTCs P0555 and P0556 (brake booster pressure sensor circuit codes) appearing in at least one complaint.
Brake line and hose ruptures are documented: flexible hoses split, fractured, or bulged near crimp fittings, causing fluid loss and sudden pedal-to-floor failure. Several owners discovered secondary hoses degrading or ready to fail. One owner notes the same hose part number was recalled on Ford Edge and Fusion models but not applied to their F-150.
A subset describes intermittent soft pedal: the brake starts firm, then progressively softens or goes to the floor mid-application. Pumping the pedal temporarily restores pressure. One owner suggests an ABS solenoid may be cycling fluid back to the reservoir instead of applying brake pressure.
Some failures occurred while parked; others at speeds of 2 to 80 mph. A few owners mention recall notifications (campaigns 20V332000, 22V150000, 23V162000, 25V236000) but reported parts unavailable for months. Repair costs mentioned range from $950 to over $2,500.
Failure modes owners describe
Master Cylinder Failure
Internal seal failure causing loss of hydraulic pressure and brake function. Fluid may leak internally or externally.
When: 4,500 to 130,000 miles; some failures within first four months of ownership
Symptoms owners cite: Brake pedal goes to the floor with no resistance or braking force; Gradual pressure loss during sustained braking; Loss of braking ability without warning lights; Brake fluid may appear full despite internal leakage; Problem may not recur immediately after repair, suggesting intermittent seal degradation
Codes mentioned: P0555 (Brake Booster Pressure Sensor Circuit), P0556 (Brake Booster Pressure Sensor Circuit Range/Performance)
Repairs/costs cited: Master cylinder replacement; some owners report replacement did not resolve issue and hydraulic control unit replacement was also required. One owner cited repair estimate over $2,500.
Recalls/TSBs owners mention: Recall 20V332000, 22V150000, 23V162000, 25V236000 (Service Brakes, Hydraulic) — but not all affected VINs were included. Dealers initially refused diagnosis or stated no recall applied. Some dealers advised problem was normal operation.
Brake Line Rupture and Hose Failure
Flexible brake hoses split, fractured, or bulged near crimp fittings, causing total or partial brake fluid loss and loss of braking.
When: 95,000 to 130,000 miles; one instance at 61,000 miles; one while parked after overnight storage
Symptoms owners cite: Brake pedal goes to the floor immediately or very soon after line rupture; Total loss of front brakes or partial loss (rear brakes only remaining); Visible fluid trail or spray from front wheel well or under vehicle; Secondary hose may be swollen or bulged at same location as ruptured hose; No warning lights prior to failure; low brake fluid warning comes after failure
Repairs/costs cited: Brake line or hose replacement. One owner cited $950 repair cost. One owner notes same part number was recalled on Ford Edge and Fusion models but not applied to F-150.
Recalls/TSBs owners mention: Dealers and manufacturer refused warranty coverage on multiple complaints; no recall applied to these vehicles despite same hose part being recalled on other Ford models. Recall 23V162000 referenced by one owner but VIN not included.
Brake Booster Failure
Loss of brake booster assist causing stiff, hard-to-depress brake pedal and/or internal fluid leakage into booster.
When: Intermittent from 2019 onward; failure at 74,862 miles; recurring at higher mileage
Symptoms owners cite: Brake pedal becomes stiff and difficult to depress; Requires standing hard on brake to stop vehicle; Loss of brake power assist; Intermittent nature; may self-resolve temporarily after pumping brakes and restarting engine; Dashboard 'Check Brake System' warning illuminates after repeated occurrences; Brake fluid may leak into booster causing low pressure
Codes mentioned: P0555 (Brake Booster Pressure Sensor Circuit), P0556 (Brake Booster Pressure Sensor Circuit Range/Performance)
Repairs/costs cited: Booster replacement; dealers reported boosters on back order for weeks to months. One owner reports dealer kept truck two months claiming inability to duplicate issue, then returned it without repair despite documented failure.
Recalls/TSBs owners mention: Dealer refused to diagnose after one intermittent occurrence and stated no recall existed. Booster part shortages cited; one owner reports manufacturer had exceeded reasonable timeframe for recall repair (Campaign 20S31 mentioned).
Soft or Progressive Brake Pedal with Loss of Pressure
Brake pedal starts firm but becomes soft or progressively sinks to the floor during continued braking, suggesting hydraulic pressure bleed-off.
When: Early mileage (5,000 to 27,000 miles reported); intermittent throughout ownership
Symptoms owners cite: Pedal feels normal initially but softens as more pressure is applied; Pedal gradually sinks to floor during sustained braking; Feeling of all hydraulic pressure bleeding off; Requires reapplication of pedal to restore braking; May occur on hills or grades where pressure loss is more apparent; Intermittent nature makes diagnosis difficult; may not be reproducible during dealer test drive
Repairs/costs cited: Master cylinder or hydraulic control unit replacement proposed. One owner was told by dealer the soft pedal was normal operation for Lariat trim trucks and could not be repaired. Another owner reports pump test with reapplication restored braking.
Recalls/TSBs owners mention: One dealer (Tindol Ford, NC) found no fault despite customer link to Recall 20V332000. Another dealer refused diagnosis. No manufacturer response documented for most cases.
ABS System Malfunction or Stuck Bypass Valve
ABS solenoid or bypass valve may be sticking or cycling improperly, causing sudden loss of braking during hard stops.
When: Starting at 7,500 miles; recurring multiple times during ownership
Symptoms owners cite: Sudden loss of brakes during hard stop; ABS unit enters bypass mode for one wheel but valve does not reset; Brake loss recurs multiple times during ownership (4+ occurrences reported); Problem resolves when ABS fuse is disabled; Loss of ABS function when fuse disabled (required safety feature compromised)
Repairs/costs cited: No factory repair found effective; owner disabled ABS by removing fuse as workaround. This eliminates mandatory ABS safety feature.
Recalls/TSBs owners mention: Ford could not isolate or fix the issue per owner. No recall or TSB documented.
Intermittent Complete Brake Failure During Driving
Brake pedal goes completely to floor with zero braking force at unpredictable times during normal driving, forcing driver to pump pedal or use emergency brake to stop.
When: Multiple occurrences ranging from first months (4,500 to 6,400 miles) through ownership; speeds from 2 to 80 mph
Symptoms owners cite: Brake pedal travels completely to floorboard with no resistance; Complete loss of braking force; vehicle does not decelerate; No warning lights or chimes prior to failure; May occur at stop signs, traffic lights, or during highway driving; Requires pumping brakes repeatedly or using emergency brake to stop; Failure is intermittent; may not recur during dealer test drive; Brake fluid reservoir may appear full despite loss of braking
Repairs/costs cited: Master cylinder, hydraulic control unit, or brake booster replacement attempted. Multiple repair attempts documented on same vehicle without resolution.
Recalls/TSBs owners mention: Recalls 20V332000, 22V150000, 23V162000, 25V236000 referenced; however, many VINs not included in recall scope. Dealers sometimes stated issue was normal operation or refused further diagnosis.
Brake Pedal Stiffness or Hard-to-Depress Pedal
Brake pedal becomes abnormally stiff or requires excessive foot pressure to depress, making normal braking difficult.
When: 27,000 miles
Symptoms owners cite: Brake pedal stiffened without warning; Difficult to depress pedal while driving at various speeds; Excessive pressure required to apply brakes
Repairs/costs cited: Defective brake booster diagnosed by second dealer; parts reported unavailable.
Recalls/TSBs owners mention: First dealer (Tindol Ford, NC) found no fault. Second dealer diagnosed defective booster but parts unavailable per NHTSA complaint records.
Brake Caliper Seizure (Rear)
Rear brake calipers seize, causing grinding noise, rapid pad and rotor wear, and reduced fuel economy.
When: Within one year of ownership (vehicle described as very new)
Symptoms owners cite: Grinding noise from brakes; Excessive wear of brake pads and rotors in short time period; Greatly reduced fuel economy due to continuous brake drag; Brakes appear to be applied while driving
Repairs/costs cited: Ford replaced one affected caliper but could not guarantee other three calipers would not fail. Failure occurred within warranty period; owner concerned about repeat failures after warranty expires.
Recalls/TSBs owners mention: Ford blamed faulty part lot but provided no expanded replacement or preventive recall.
False Brake System Warning Messages
Dashboard warning messages (Check Brake System, Park Brake Malfunction) appear intermittently without actual brake failure or persist after repair attempts.
When: Intermittent from day after delivery through extended ownership; 40,000+ miles
Symptoms owners cite: 'Check Brake System' warning on dashboard; 'Park Brake Malfunction—Service Now' message with brake system symbols; Multiple random occurrences, can happen at startup, while running, or any operating condition; Warnings may clear after restarting vehicle; Persistence despite multiple repair attempts
Repairs/costs cited: Multiple dealer service attempts (documented as many as 6) without resolution. One owner received recall notification (Campaign 25V236000) but parts unavailable.
Recalls/TSBs owners mention: Recall 25V236000 issued but parts not available for extended period per owner complaint.
Synthesized from 59 NHTSA owner complaints — unverified consumer
allegations, summarized for patterns. The verbatim filings appear below.