Complete transmission failure on the 2009 GMC Acadia
When complete transmission failure gets reported
Owners of the 2009 GMC Acadia report complete transmission failure at a median of 90,000 miles. A quarter of the reports come in before 75,000 miles and a quarter after 105,000 miles, from 17 reports that carried an odometer reading.
A part like this is normally expected to survive 98,000 miles. It is the 9th most-reported problem on this model year.
The mileage distribution
The reported range runs from 70,000 miles at the tenth percentile to 125,000 miles at the ninetieth, a spread of 58,499 miles across the middle 80% of reports.
A window that narrow is the signature of a part that fails on its own schedule rather than on how the car is driven — which is usually a design or supplier problem rather than wear and tear.
0% of the dated reports were filed under 36,000 miles.
The whole distribution
| 10th | 25th | Median | 75th | 90th |
|---|---|---|---|---|
| 68,800 miles | 75,000 miles | 92,000 miles | 105,000 miles | 127,299 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 $2,800–$8,000 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.
This mode is classified as critical, which means a failure can leave the car unable to stop, steer, or stay out of the way of traffic. It is weighted accordingly in the risk score.
The same failure on other years
The same failure is reported on 9 model years of this car. It shows up earliest on the 2023, at a median of 5,000 miles, and latest on the 2012 at 120,000 miles.
By volume the 2008 carries the most reports, with 89; the 2009 has 17. 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.
My wife was driving her 09 acadia and all of a sudden it quit shifting and the engine revved up if she went over 25 MPH. She limped it to a local service station where they informed us that the reverse clutch pressure plate was broken and needed a new transmission. Even though it was within gm's 5yr 100k "powertrain warranty", they "conveniently" excluded that problem from being covered. I have seen many, many complaints regarding this issue and it is[xxx] that gm isn't owning up to it and correcting the problem on current vehicles. So, now we are out $3500 for a new transmission on a car with only 75k miles! Information redacted pursuant to the freedom of information act (foia), 5 u.s.c. 552(b)(6). *tr *updated 1/15/2014 *js
While driving thru an intersection with a yield my vehicle suddenly stopped and the engine RPM climbed to around 3500 RPM. The transmission slipped between gears causing a sudden and unexpected slow down.luckily another driver was alert and had to slow down quickly to keep from hitting us as we were merging with traffic.this never happened before and came on without warning.as soon as it happened once it has been happening more often, I brought the vehicle in and the diagnosis was the "wave plates" in the transmission. The mechanic informed me that this transmission had an issue with a part that was not properly heat treated and caused it to fail.I called the gm dealer and they would not warranty because we were just outside the 100,000 mile warranty period. They also stated that they knew there have been many issues with this vehicle but gm has not issued any type of recall.now I need a new transmission at a cost of around 4,000 dollars. I have owned several gm vehicles in the past and gotten well over 250,000 miles with no issues at all. This could have been very serious and caused injuries if the circumstances were different…
Current issue is a transmission failure, apparently the "3-5-r waveplate." five months prior, my wife and children were traveling out of state. They experienced a sudden loss of power and were stranded on a rural highway not once, but twice. The vehicle was towed in to a gm dealership, "repairs" were performed under warranty, and we were told we could pick up our car. My wife (again with children in the car) made it less than 10 miles from the dealership before the engine failed again. This time on the bridge of a major highway....no where to even exit the vehicle. After the second incident the engine was replaced (after 3+ weeks of diagnostic work). We were told the dealership was not able to identify the problem that caused the engine failure. Engine was replaced under warranty. Transmission had been shifting erratically for several months. At time of engine failure/replacement, gm dealership that performed the engine replacement advised us that the transmission shifts/slips were "normal" for this particular transmission. They advised a transmission fluid flush, which we authorized. Shifting remained abrupt, slipping continued…
Also reported on the 2009 GMC Acadia
Other steering problem
Timing chain, belt or tensioner failure
Steering rack, gear or tie rod failure
Other powertrain problem
Other engine problem
Headlight failure or clouding
How far this goes
Complaints are voluntary, so 17 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 complete transmission failure happen on the 2009 GMC Acadia?
Across 17 owner reports that included an odometer reading, half were filed by 90,000 miles. A quarter were filed before 75,000 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 complete transmission failure on the 2009 GMC Acadia?
17 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