Unclassified problem on the 2012 GMC Terrain
9 crashes 6 injuries 15 of the 31 reports for this failure mention a crash, a fire, an injury or a death. Those are the owner's words on the complaint form, not a verified finding, and one report can mention more than one.
Only 20 reports for this mode came with an odometer reading, which is too few for percentiles to mean anything. The page is here because someone linked to it; treat the figures as anecdotes, and see the full report for this year instead.
When unclassified problem gets reported
Owners of the 2012 GMC Terrain report unclassified problem at a median of 70,000 miles. A quarter of the reports come in before 55,000 miles and a quarter after 100,000 miles, from 20 reports that carried an odometer reading.
It is the 50th most-reported problem on this model year.
The mileage distribution
The reported range runs from 25,000 miles at the tenth percentile to 125,000 miles at the ninetieth, a spread of 100,810 miles across the middle 80% of reports.
A spread this wide points at use rather than design. Towing, climate, service history and city mileage all move a failure like this, so the median is a weak guide to any individual car.
25% of the dated reports were filed under 36,000 miles.
The whole distribution
| 10th | 25th | Median | 75th | 90th |
|---|---|---|---|---|
| 26,290 miles | 52,500 miles | 71,615 miles | 99,750 miles | 127,100 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
Of these reports, 9 a crash and 6 an injury are mentioned. Owners write their own complaints and the agency does not verify them, so read this as what the reports say happened rather than as a confirmed count.
The same failure on other years
The same failure is reported on 12 model years of this car. It shows up earliest on the 2018, at a median of 5,000 miles, and latest on the 2012 at 70,000 miles.
By volume the 2011 carries the most reports, with 33; the 2012 has 31. A mode that appears across most years of a model is usually a design choice rather than a bad batch.
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.
Tl* the contact owns a 2012 gmc terrain. The contact stated that he fell asleep while driving an unknown speed. The vehicle traveled to the right side of the road and went airborne approximately 20 feet, landing on all four tires. The vehicle then traveled approximately 200 feet and crashed into an embankment. The air bags failed to deploy. The contact sustained a fractured back as a result. A police officer witnessed the incident and filed a report. The vehicle was destroyed and towed to a collision center. The manufacturer was not notified of the faulty air bags. The approximate failure mileage was 7,000. Updated 10/16/12*lj
Tl* the contact owns a 2012 gmc terrain. The contact stated that while sitting at a traffic stop, a semi-truck crashed into the rear bumper of the contact's vehicle. The contact's vehicle was pushed forward, causing the contact to crash into a preceding vehicle. The air bags failed to deploy. The contact sustained injuries to the hand, neck and back. A police report was filed. The vehicle was towed to an independent mechanic for diagnosis but they were unable to duplicate the air bag deployment failure. The manufacturer was notified of the failure. The VIN was not available. The approximate failure mileage was 32,000. *tr
I inadvertently veered off side roadway, (va highway 220) colliding with a tree/roadside shrubs, etc (was knocked unconscious as forehead hit steering wheel on initial impact). Airbags did not deploy allowing me to sustain a head injury that knocked me unconscious... Forehead was gashed with significant bleeding. I was transported by ambulance in unconscious state. Damage to vehicle is in excess of $8,000 so far as vehicle still in repair shop with massive front end damage that affects steering linkage, etc. The impact of vehicle against foliage, trees shrubs, should have forced air bags to deploy and I believe that I would not have sustained a head injury that rendered me unconscious with mild concussion and could not control vehicle leaving roadway. *tr
Also reported on the 2012 GMC Terrain
Excessive oil consumption
Other engine problem
Timing chain, belt or tensioner failure
Wiper or washer failure
Other visibility problem
Other electrical problem
How far this goes
This page is kept out of search results because 31 reports is not enough to publish percentiles from. It stays reachable because somebody looking at this exact car would rather see the reports than be told there are none.
Complaints are voluntary, so 31 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 unclassified problem happen on the 2012 GMC Terrain?
Across 20 owner reports that included an odometer reading, half were filed by 70,000 miles. A quarter were filed before 55,000 miles and a quarter after 100,000 miles. These are the mileages owners reported when they complained, not a prediction for any individual car.
How common is unclassified problem on the 2012 GMC Terrain?
31 reports have been filed with NHTSA, about 0.3 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