Rust or structural corrosion on the 2003 GMC Sierra 1500
When rust or structural corrosion gets reported
Owners of the 2003 GMC Sierra 1500 report rust or structural corrosion at a median of 70,000 miles. A quarter of the reports come in before 45,000 miles and a quarter after 105,000 miles, from 13 reports that carried an odometer reading.
A part like this is normally expected to survive 120,000 miles. It is the 5th most-reported problem on this model year.
The mileage distribution
The reported range runs from 45,000 miles at the tenth percentile to 140,000 miles at the ninetieth, a spread of 96,781 miles across the middle 80% of reports.
When the reports scatter this far, the mileage is telling you about how these cars were driven more than about the part itself.
8% of the dated reports were filed under 36,000 miles.
The whole distribution
| 10th | 25th | Median | 75th | 90th |
|---|---|---|---|---|
| 44,300 miles | 44,300 miles | 72,000 miles | 104,000 miles | 141,081 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 $500–$6,000 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.
The same failure on other years
The same failure is reported on 10 model years of this car. It shows up earliest on the 2006, at a median of 55,000 miles, and latest on the 1999 at 150,000 miles.
By volume the 2003 is the worst of them, which makes this a problem of this specific year rather than of the model as a whole.
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.
Corroded brake lines on 2003 gm sierra 1500 long box pickup truck. First failure was in january 2009. Second failure in february 2010. When truck was inspected in nov. 2009, inspector indicated that gm truck brake lines are a known safety hazard. He looked over mine, but did see evidence of need for immediate repair. Truck was bought new in oct. 2003 by me, and now has only 24,500 original miles on it. Gm should most definitely be required to recall these vehicles and replace all corrosion-prone brake lines with corrosion-proof ones. There is no greater safety concern than braking. I am taking truck to have all lines replaced at my expense, in the interest of my and others' safety. But, gm should not be allowed to foist junk with massive safety consequences upon consumers and get to walk away from it. The potential here makes the toyota gas pedal problem seem like a trivial joke! *tr
Tl* the contact owns a 2003 gmc sierra 1500. The vehicle was taken to a state inspection station where the contact was informed by the technician that the brake lines exhibited severe rust. The dealer was notified of the failure but because the vehicle was outside of warranty, the vehicle was not repaired. In addition, the contact stated that the main frame also exhibited rust and corrosion. The contact was in the process of taking the vehicle to an independent mechanic for repair. The VIN was unavailable. The failure mileage was 72,000.
Tl* the contact owns a 2003 gmc sierra 1500. The vehicle was taken to a state inspection station where the contact was informed by the technician that the brake lines exhibited severe rust. The dealer was notified of the failure but because the vehicle was outside of warranty, the vehicle was not repaired. In addition, the contact stated that the main frame also exhibited rust and corrosion. The contact was in the process of taking the vehicle to an independent mechanic for repair. The VIN was unavailable. The failure mileage was 72,000.
Also reported on the 2003 GMC Sierra 1500
Instrument cluster or gauge failure
Loss of braking
Brake line, hose or caliper failure
Other brake problem
ABS module or sensor failure
Steering rack, gear or tie rod failure
How far this goes
Complaints are voluntary, so 14 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 rust or structural corrosion happen on the 2003 GMC Sierra 1500?
Across 13 owner reports that included an odometer reading, half were filed by 70,000 miles. A quarter were filed before 45,000 miles and a quarter after 105,000 miles. These are the mileages owners reported when they complained, not a prediction for any individual car.
How common is rust or structural corrosion on the 2003 GMC Sierra 1500?
14 reports have been filed with NHTSA, about 14 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