Complete transmission failure on the 2008 Pontiac G6
Only 5 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 complete transmission failure gets reported
There are 5 reports of complete transmission failure on the 2008 Pontiac G6, 5 with a mileage attached. That is too few to place the failure on the odometer with any confidence.
A part like this is normally expected to survive 98,000 miles. It is the 39th most-reported problem on this model year.
The whole distribution
| 10th | 25th | Median | 75th | 90th |
|---|---|---|---|---|
| — | — | 65,700 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 5 model years of this car. It shows up earliest on the 2006, at a median of 40,000 miles, and latest on the 2007 at 80,000 miles.
By volume the 2009 carries the most reports, with 7; the 2008 has 5. 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.
Was driving and, car started to shake and kept missing gears. Rpms were up, exhaust was up but car would not catch and when I was going to park my car in the garage my car would not reverse at all, so I had to push it into the garage. Upon speaking with several pontiac g6 owners, it is said that the 3,5 r wave plate was very weak, which made this transmission prone to failure in gm products. Updated wave plates were released for clutches in 6t70, the old design wave plates weren't stress relieved and could break with use. For it just being a $10 part this is outrageous that I would need to get a whole new transmission which costs 2-3k. Something needs to be done about this immediately before anyone gets hurt. *js
Was driving and, car started to shake and kept missing gears. Rpms were up, exhaust was up but car would not catch and when I was going to park my car in the garage my car would not reverse at all, so I had to push it into the garage. Upon speaking with several pontiac g6 owners, it is said that the 3,5 r wave plate was very weak, which made this transmission prone to failure in gm products. Updated wave plates were released for clutches in 6t70, the old design wave plates weren't stress relieved and could break with use. For it just being a $10 part this is outrageous that I would need to get a whole new transmission which costs 2-3k. Something needs to be done about this immediately before anyone gets hurt. *js
I have owned this car since new. All service work was performed on time. 6t70 6 speed automatic transmission failed while taking my kids to school. No warning and slipped into neutral while driving. None of the drive gears would work. Lucky we were able to pull over without incident. We were traveling on a secondary road at 45 MPH and could have been rear ended! Took car to dealer and they wanted $800 to diagnose what was wrong with the transmission. Called gm customer relations, but they were not helpful since my car was out of warranty. Car had 5 year 100k warranty, but my car with low mileage was too old. This repair will cost me $3300 from a private shop. Gm products are terrible. This 6t70 transmission is in gmc acadia, buick enclave, chevrolet traverse, ford explorer, and several other gm/ford models. Should be recalled for bad reliability and safety! *tr
Also reported on the 2008 Pontiac G6
Other steering problem
Cruise control failure
Headlight failure or clouding
Other electrical problem
Other lighting problem
Other brake problem
How far this goes
This page is kept out of search results because 5 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 5 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 2008 Pontiac G6?
Across 5 owner reports that included an odometer reading, half were filed by 65,000 miles. A quarter were filed before — and a quarter after —. These are the mileages owners reported when they complained, not a prediction for any individual car.
How common is complete transmission failure on the 2008 Pontiac G6?
5 reports have been filed with NHTSA, about 0.0 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