This service bulletin provides information on some vehicles that may rock or move slightly forward or rearward while in Park at start up after cold soak. This condition may be accompanied by a clunk noise. This is a slight movement that is more often seen visually, rather than felt, when viewed from the outside and using the auto-start feature, if equipped.
full bulletin at NHTSA ↗2009 Pontiac G8 powertrain problems
moderate 7 complaints filed with NHTSA · avg repair $2,500 · see powertrain across all vehicles →
Complaints
7
Recalls
0
Avg fix
$2,500
When does it fail?
Of the 7 powertrain complaints filed for the 2009 Pontiac G8, here's the actual mileage breakdown — failures cluster heaviest at 0-25,000 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 powertrain complaint has been filed on this vehicle in over 9 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 powertrain 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 bulletin provides information on the harmful effects of water or ethylene glycol in transmission fluid.
full bulletin at NHTSA ↗This service bulletin provides technicians with information to help identify the differences between what is considered a fluid leak, and what is considered fluid seepage.
full bulletin at NHTSA ↗This PI bulletin advises the technician on the proper way to install the pistons in an engine.
full bulletin at NHTSA ↗This bulletin advises the technician that the 6L50 (MYB), 6L80 (MYC) and 6L90 (MYD) Transmission Oil Filter and Seal Kit part number 24236933 is currently transitioning from a kit to the filter (24236517) and seal (24225347) being sold individually.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
What owners are reporting 3 most recent
Left front wheel bearing ass'y has been replaced twice because of moan/roaring noise that increases and decreases as speed increases and decreases. Noise becomes noticeably louder as you make a right hand turn - which causes the left front wheel to have an increase in weight bearing. Original replaced @ 78,042 miles. First replacement become so noisy that it was replaced @ 79,264 miles. Noise…
Tl* the contact owns a 2009 Pontiac g8, with a 6 speed transmission. He can shift from first to second gear only when driving between 15 to 20 MPH. Consequently the vehicle would shift from 1st to 4th gear. A technician from the dealer stated that the failure was a normal characteristic for that model type. The Pontiac manufacturer was notified, but no assistance was provided. The failure…
Automatic transmission fails to immediately downshift when accelerating to merge into traffic, leaving car and driver in precarious predicament with today's highway speeds. Transmission also causes a vibration when speed decreases and causes dod to be implemented. Dealer has no solution. *tr
Had powertrain trouble with your 2009 Pontiac G8?
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 powertrain problem on the 2009 Pontiac G8?
It's a documented issue but not catastrophic. 7 complaints have been filed. Repairs average $2,500 and most owners catch it before it causes a breakdown.
At what mileage does the powertrain typically fail?
Based on the 7 complaints filed, powertrain issues most often appear around 52,978 miles. Some report problems earlier; some make it well past 150,000 with no symptoms. Maintenance habits matter — vehicles that received timely fluid services and were not regularly overworked tend to last longer.
What does it cost to fix?
Independent shops typically charge around $2,500 for powertrain 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 powertrain?
No active recalls currently cover powertrain 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/2009/Pontiac/G8.
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.