This technical bulletin provides information and a solution to a condition of Brake Pedal Moves or Self Applies at Full Turns.
full bulletin at NHTSA ↗2005 Hummer H2 brakes problems
moderate 11 complaints filed with NHTSA · avg repair $450 · see brakes across all vehicles →
Failure mileage
Complaints
11
Recalls
0
Avg fix
$450
When does it fail?
Of the 11 brakes complaints filed for the 2005 Hummer H2, 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
No new NHTSA brakes complaint has been filed on this vehicle in over 10 years — the issue may be aging out of the active population.
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.
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 ↗This Preliminary Information communicates to the dealer the process for downloading or updating operating software for the Tire Pressure Monitor, Active Fuel Injector tester, multi media tester, PICO Scope, GR8 starting/charging tester and Vehicle Data Recorder tools, giving website address and step by step instructions to complete the update.
full bulletin at NHTSA ↗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 ↗This Preliminary Information communication provides information to the technician about changing the tire and wheel size on vehicles. General Motors will only support a tire calibration for tires that have been sized, tested and designed for the vehicle in question and its applications. Technician should not use the information that is provided by the antilock braking system tire size selection.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
Brake failures on 2005 Hummer H2 models cluster around two main defects: corroded and ruptured brake lines, and failed brake boosters and accumulators.
Brake line corrosion shows up as soft or floor-mounted brake pedals accompanied by visible fluid leaks from the rear lines or under the vehicle. One owner's steel brake line burst outright due to rust; another lost all braking at a red light when rusted lines failed simultaneously (the dual-system redundancy didn't help because both circuits were compromised). Repairs ran $1,100 to $1,949 for line replacement. Owners cite galvanic corrosion as the likely cause — incompatible materials corroding faster than normal.
Brake booster problems manifest as stiff pedals, loss of braking response, difficulty steering under braking, and whining or whistling noises from the engine bay. One owner's brakes failed when shifting into gear; another experienced intermittent pedal-to-floor episodes that vanished without repair. Failures occurred between 70,000 and 140,000 miles.
Brake booster accumulator cracking caused intermittent brake loss with squeaking, diagnosed at 81,500 miles.
Hydro-boost leaks (where the brake system shares pressurized fluid with power steering) appeared at 75,000 miles.
GM issued recall campaigns 05V043000 and 04V045000 for hydraulic brake issues, but most complainants' VINs were excluded. Dealers have refused warranty coverage on corroded lines, citing normal wear on vehicles near 10 years old.
Failure modes owners describe
Brake line corrosion and rupture
Steel brake lines corrode and rust through, causing loss of brake fluid pressure and complete or near-complete brake failure. Owner #1 attributed this to galvanic corrosion from wrong material choices by GM engineers. Owner #10 experienced a steel brake line burst due to corrosion and rust, resulting in brake pedal to floor.
When: 73,600 to 140,000 miles; owner #4 at ~10 years age
Symptoms owners cite: Brake pedal goes to floor or very soft; Brake fluid leaking from rear brake lines or under vehicle; Complete loss of braking while stopping or turning; No reserve braking from dual system
Repairs/costs cited: Owner #1 replaced all brake lines at $1,100. Owner #4 replaced rear and front brake lines at $1,949. Owner #10 had vehicle towed; GM service center denied warranty coverage due to age.
Recalls/TSBs owners mention: No recall identified for affected VINs. Manufacturer stated vehicle age (almost 10 years) was considered normal life expectancy for this component.
Brake booster malfunction
Brake booster fails or malfunctions, causing loss of power assist. Owners reported symptoms consistent with NHTSA recall 05V043000, but their VINs were not included in that recall campaign.
When: 70,000 to 140,000 miles
Symptoms owners cite: Brake pedal becomes very stiff or hard; Brakes fail to respond when pedal is depressed; Difficulty steering (power steering affected when brakes engaged); Vehicle rolls forward even with brake pedal firmly depressed; Whining noise from engine compartment; Whistling sound from brakes
Repairs/costs cited: Dealers/mechanics diagnosed brake booster replacement needed. Owner #7 problem was intermittent and resolved spontaneously without repair. Owner #9 was not repaired.
Recalls/TSBs owners mention: NHTSA recall 05V043000 (Service Brakes, Hydraulic) exists but affected VINs excluded from campaign. Manufacturer confirmed no recall for specific VINs.
Brake booster accumulator cracking
Hydraulic brake booster pressure accumulator cracks, causing brake system pressure loss and intermittent brake failure.
When: 81,500 miles
Symptoms owners cite: Brakes fail to respond when pedal depressed; Abnormal squeaking sound from steering wheel area; Intermittent brake failures
Repairs/costs cited: Independent mechanic replaced hydraulic brake booster accumulator.
Recalls/TSBs owners mention: VIN not included in NHTSA recall 05V043000 (Service Brakes, Hydraulic).
Brake hydro-boost fluid leakage
Brake hydro-boost system leaks fluid, typically power steering fluid mixing with brake system. Related to but distinct from brake line corrosion.
When: 75,000 miles
Symptoms owners cite: Power steering fluid leakage detected underneath vehicle; Brake hydro-boost leaking
Repairs/costs cited: Vehicle not repaired by owner.
Recalls/TSBs owners mention: Related to NHTSA recall 04V045000 (Service Brakes, Hydraulic), but affected VIN was not included in that recall.
Synthesized from 11 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 2 most recent
Tl* the contact owns a 2005 Hummer h2. The contact stated that while coming to a stop, the brakes failed to respond when the brake pedal was depressed. In addition, an abnormal squeaking sound was heard from the steering wheel. The failure recurred intermittently. The vehicle was taken to an independent mechanic where it was diagnosed that the hydraulic brake booster accumulator cracked and…
Tl* the contact owns a 2005 Hummer h2. The contact stated that while driving at various speeds, the steering wheel became difficult to turn. The contact also stated that there was fluid on the ground. The vehicle was taken to an independent mechanic where it was diagnosed that the power steering pump needed to be repaired. The vehicle was not repaired. The manufacturer was made aware of the…
Had brakes trouble with your 2005 Hummer H2?
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 2005 Hummer H2?
It's a documented issue but not catastrophic. 11 complaints have been filed. Repairs average $450 and most owners catch it before it causes a breakdown.
At what mileage does the brakes typically fail?
Across the 10 complaints that reported odometer mileage, most brakes failures cluster between 73,600 and 130,000 miles, with the median around 81,500. A quarter of owners report trouble before 73,600; a quarter make it past 130,000. 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/2005/Hummer/H2.
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.