The cv axle assemblies snap like the 2016 models do Kia's recall number sc139.
2018 Kia Optima powertrain problems
severe 18 complaints filed with NHTSA · avg repair $2,500 · see powertrain across all vehicles →
Failure mileage
Complaints
18
Recalls
0
Avg fix
$2,500
1crash
1fire
2injuries
When does it fail?
Of the 18 powertrain complaints filed for the 2018 Kia Optima, here's the actual mileage breakdown — failures cluster heaviest at 50,000-75,000 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 6 years — the issue may be aging out of the active population.
What owners are reporting 1 most recent
Had powertrain trouble with your 2018 Kia Optima?
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 2018 Kia Optima?
It's a meaningful issue. 18 complaints have been filed and the failure mode causes operational problems for owners. Repairs average $2,500.
At what mileage does the powertrain typically fail?
Across the 8 complaints that reported odometer mileage, most powertrain failures cluster between 14,770 and 63,000 miles, with the median around 30,500. A quarter of owners report trouble before 14,770; a quarter make it past 63,000. Maintenance history matters more than the odometer alone — this is the reported failure window, not a guarantee.
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/2018/Kia/Optima.
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.