This Preliminary Information communication advises the technician that the Hydro-Boost is not serviceable and will need to be replaced if the brake pedal moves or applies on its own at a full turn.
full bulletin at NHTSA ↗2014 GMC Sierra brakes problems
severe 118 complaints filed with NHTSA · avg repair $450 · see brakes across all vehicles →
Failure mileage
Complaints
118
Recalls
0
Avg fix
$450
8crashes
2injuries
When does it fail?
Of the 118 brakes complaints filed for the 2014 GMC Sierra, here's the actual mileage breakdown — failures cluster heaviest at 50,000-75,000 mi.
0-25k
25-50k
50-75k
75-100k
100-125k
125-150k
150k+
Each bar shows the share of total complaints filed at that mileage range. Peak failure window highlighted. Some owners report problems earlier; some make it well past 150,000 miles symptom-free. Maintenance habits and driving conditions shift the curve as much as mileage alone.
What stands out
Owners have filed 118 brakes complaints with NHTSA against this vehicle, but no formal recall covers the issue — the federal record reflects what manufacturers have admitted, not everything owners are reporting.
Among the 19 model years of GMC Sierra in our records for brakes problems, this one ranks #2 by owner-complaint volume.
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering brakes on this vehicle — documented repair instructions, service campaigns, or warranty extensions sent to dealers. A TSB isn't a recall (it's not a free safety remedy), but it's the manufacturer acknowledging the issue and how to fix it.
SUMMARY TO BE PROVIDED ON A FUTURE DATE.
full bulletin at NHTSA ↗SUMMARY TO BE PROVIDED ON A FUTURE DATE.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
Owners report a pattern of power-brake loss on 2014 GMC Sierra 1500s, typically at low speeds or during extended stop-and-go driving. The brake pedal becomes hard or unresponsive, forcing drivers to press with extreme force—sometimes both feet—to stop. This happens most often during parking, reversing (especially boat or trailer backing), or after prolonged idle periods in traffic. The problem emerges unpredictably and may reset after engine shutdown and restart. Some owners experience it after highway driving followed by parking-lot maneuvers.
Owners identify the culprit as the vacuum pump, citing GM service bulletin PIT5361 and technical directives that discuss weak vacuum at the brake booster. Several note that oil seal failure in the pump can contaminate the vacuum line, brake booster, and master cylinder, requiring replacement of multiple components. Owners report repair costs ranging from $350 to over $1,600 depending on contamination scope.
The problem recurs even after recall repairs (NHTSA 19V645000) in some vehicles, suggesting the original fix may not address the root cause. Owners report instances of near-crashes and actual collisions. A few mention that physical strength matters—drivers unable to apply extreme pedal pressure cannot brake adequately, particularly dangerous when towing or with children aboard.
Same GMC Sierra brakes reports on nearby years: 2015 · 2017
Failure modes owners describe
Vacuum pump failure causing loss of power brake assist
The belt-driven vacuum pump degrades or fails entirely, reducing vacuum pressure to the brake booster. Without adequate vacuum, power assist is lost, making the brake pedal extremely hard to depress and drastically reducing stopping power. The condition may be intermittent initially, then worsen, and sometimes corrects temporarily after engine restart.
When: Typically 40,000 to 190,000 miles; most commonly reported around 65,000–90,000 miles
Symptoms owners cite: Brake pedal becomes very hard or stiff to depress; Stopping power severely reduced; requires extreme force on pedal; Brake assist warning light illuminates (in some cases); Condition worsens during stop-and-go traffic or after prolonged braking; Intermittent loss of brakes that may resolve after engine restart; Problem triggered or exacerbated in reverse, especially backing boats or trailers downhill; Brake pedal may travel far or press to floorboard without adequate stopping effect; Grinding or squeaking sounds during hard braking attempts
Codes mentioned: GM Service Bulletin PIT5361B (weak vacuum at brake booster), NHTSA Campaign 19V645000 (Service Brakes, Hydraulic), Service Brake Assist warning indicator
Repairs/costs cited: Owners report vacuum pump replacement costs of $350–$1,000+. If oil leaks past pump seals, brake booster, master cylinder, vacuum lines, and serpentine belts may require replacement, raising total cost to $1,600+. Labor-intensive; requires removal of oil pan debris in some cases.
Recalls/TSBs owners mention: GM issued Service Bulletin PIT5361 describing pump replacement procedure. NHTSA Recall 19V645000 addressed some vehicles; however, owners report the recall fix does not fully resolve the problem in many cases, with brake failures recurring after recall repair. Recall coverage has expired for many vehicles over 100,000 miles. Warranty denials reported when mileage exceeds coverage thresholds.
Brake booster vacuum leak or sensor malfunction
The brake booster or its vacuum sensor develops a large leak, or the sensor fails to detect vacuum loss. Either condition starves the booster of vacuum pressure, eliminating power assist and requiring extreme pedal pressure to brake.
When: Variable; reported at 23,000 miles and upward
Symptoms owners cite: Brake pedal becomes abnormally stiff or difficult to depress; Reduced stopping power requiring double-foot pressure; Loss of power braking sensation (feels like mechanical brakes with no assist); Service Brake Assist warning light may illuminate; Problem occurs unpredictably, especially at low speeds or in parking situations
Codes mentioned: Service Brake Assist warning light, Brake booster vacuum leak (diagnosed by dealer/mechanic)
Repairs/costs cited: Booster replacement or vacuum line repair; some owners cite costs exceeding $400. Parts described as uncommonly replaced, leading to supply delays.
Recalls/TSBs owners mention: Dealers have identified brake booster vacuum issues and recommended replacement. Some dealers deny warranty coverage, citing normal wear. Manufacturer acknowledgment is inconsistent.
Master cylinder or hydraulic system compromise
After prolonged vacuum pump oil leakage, the master cylinder may become contaminated or fail. Owners report needing master-cylinder replacement in conjunction with vacuum pump repair when oil has entered the vacuum circuit.
When: Follows vacuum pump failure; occurs once pump seal degradation has allowed oil migration
Symptoms owners cite: Brake pedal becomes very hard after pump failure; Braking fails or becomes extremely difficult even with dual-foot pressure; May occur only after longer drives or sustained braking cycles
Repairs/costs cited: Master cylinder replacement can cost $200–$500+. Required only if oil contamination is present; some repairs avoid this cost if caught early.
Recalls/TSBs owners mention: GM Service Bulletin PIT5361B warns that oil escape from a failing pump may necessitate master-cylinder replacement alongside booster and vacuum line replacement.
Synthesized from 118 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 4 most recent
Lost normal braking going down a steep hill at 25 MPH , had to use both feet on the brake pedal just to stop.
Hello, I am driving a 2014 Sierra truck with 17,761 miles, my father’s work truck. The first week I had No problems, the 2nd week the Trailer Brake warning came on relentlessly. New truck, scary Warning sign! I took it to GMC to dislocate trailer brake, they sold me a $340 trailer brake control switch. Upon my return to where I live a loud sound came from when I was idling to wait for…
While in motion, applied brakes and the pedal went to the floor without stopping. Checked brake fluid and it was near empty. Only 50,000miles.
This vehicle has the same issue as other recalled GMC Sierra vehicles - the brake booster pump is failing, causing braking difficulty, particularly at low RPM and after repeated presses of the brake pedal.
Had brakes trouble with your 2014 GMC Sierra?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the brakes problem on the 2014 GMC Sierra?
It's a meaningful issue. 118 complaints have been filed and the failure mode causes operational problems for owners. Repairs average $450.
At what mileage does the brakes typically fail?
Across the 93 complaints that reported odometer mileage, most brakes failures cluster between 57,000 and 102,000 miles, with the median around 72,508. A quarter of owners report trouble before 57,000; a quarter make it past 102,000. Maintenance history matters more than the odometer alone — this is the reported failure window, not a guarantee.
What does it cost to fix?
Independent shops typically charge around $450 for brakes repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to brakes?
No active recalls currently cover brakes issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2014/GMC/Sierra.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.