TECHNICAL SERVICE BULLETIN: TRANSMISSION FLUID APPLICATION GUIDE - This bulletin has been revised to include additional information. New/revised sections of this bulletin are indicated by a black bar in the margin area. This bulletin provides information relating to the correct transmission fluid type and fill quantity requirement for each Kia model. A flush is required ONLY when a transmission is replaced, and the transmission oil cooler is transferred to the new transmission.
full bulletin at NHTSA ↗2012 Kia Forte powertrain problems
moderate Owners of the 2012 Kia Forte have filed 10 NHTSA complaints about the powertrain, typically surfacing around 80,000 miles at roughly $2,500 to repair (U.S. federal records, as of July 2026). Source: NHTSA Office of Defects Investigation. See powertrain across all vehicles →
Failure mileage
Complaints
10
Recalls
0
Avg fix
$2,500
| Model year | powertrain complaints |
|---|---|
| 2010 Forte | 20 |
| 2011 Forte | 19 |
| 2012 Forte (this page) | 10 |
| 2013 Forte | 9 |
| 2014 Forte | 16 |
| 2015 Forte | 17 |
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 relating to the correct transmission fluid type and fill quantity requirement for each Kia model. A flush is required ONLY when a transmission is replaced.
full bulletin at NHTSA ↗TECHNICAL SERVICE BULLETIN: TRANSMISSION FLUID APPLICATION GUIDE - This bulletin provides information relating to the correct transmission fluid type and fill quantity requirement for each Kia model. A flush is required ONLY when a transmission is replaced, refer to applicable vehicles in the chart starting on page 2.
full bulletin at NHTSA ↗TECHNICAL SERVICE BULLETIN: - TRANSMISSION FLUID APPLICATION GUIDE - This bulletin has been revised to include additional information. This bulletin provides information relating to the correct transmission fluid type and fill quantity requirement for each Kia model. A flush is required ONLY when a transmission is replaced, refer to applicable vehicles on page 2. Refer to the shop manual on KGIS for the specific Kia model for the correct transmission fluid check/fill procedures.
full bulletin at NHTSA ↗TSB: 6-SPD. A/T ADAPTIVE VALUE RESET /RELEARN - THIS BULLETIN PROVIDES THE PROCEDURES NECESSARY TO RESET AND RELEARN THE ADAPTIVE VALUES AFTER TRANSMISSION REPLACEMENT OR REPROGRAMMING/REPLACEMENT OF THE PCM/TCM. AFTER THE ADAPTIVE VALUES ARE RESET, THE TRANSMISSION COMPUTER ADAPTIVE VALUES MUST BE RELEARNED BY DRIVING IN A PRECISE MANNER TO TEACH THE COMPUTER THE PROPER SOLENOID DUTY AND LINE PRESSURE FOR THE NEW TRANSMISSION/COMPUTER COMBINATION.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
The 2012 Kia Forte powertrain carries multiple failure modes. Engine knock is the most common complaint—owners hear loud pinging or clunking at cold start and idle across a wide mileage range, often tied to the Theta II engine and pinpointed as a connecting rod or bearing issue. At least one owner reported catastrophic engine failure with the rod going through the block at 105,000 miles, which Kia was slow to repair. Several owners note this knock is a known defect with no recall, despite identical issues triggering recalls on other Kia engines.
Shift lock failure is another safety concern: multiple owners report the gear shifter disengaging from park without brake pedal pressure. One owner's car rolled into the street with the engine off and no key in the ignition. Kia denied this was a safety issue.
Transmission problems include the cable slipping off or an unknown part disconnecting near the gearshift, causing the shifter to seize. Brake lights fail intermittently or stay on continuously, and bulbs fracture immediately after replacement. A traction control light also illuminates continuously on one vehicle. One owner reported the motor shutting down at highway speed with no warning lights.
Same Kia Forte powertrain reports on nearby years: 2010 · 2011 · 2014 · 2015
Failure modes owners describe
Engine knock and knocking noise on cold/warm starts
Owners report loud knocking, pinging, or diesel-like engine noise at startup and during idle that persists at running temperature. Multiple owners identify this as a connecting rod or connecting rod bearing issue, specifically related to the Theta II engine. The noise increases with idle speed and can be accompanied by engine stall.
When: At startup and during idle; reported across mileages from 77,000 to 100,000+ miles; complaint #3 noted issue beginning March 2020
Symptoms owners cite: Loud knocking or pinging noise on cold start; Noise persists at running temperature; Noise increases with idle speed; Engine sounds like diesel engine; Loud clunking sound while starting; Engine stalling risk during highway driving
Repairs/costs cited: One dealer told owner full engine replacement was required at 77,000 miles. Complaint #6 involved rod failure requiring engine repair; rod knock reported a week before engine failure. Multiple owners report this is a known defect with no recall issued.
Recalls/TSBs owners mention: Multiple dealers confirmed common issue with similar vehicles; Kia stated this was not a safety issue; no recall issued despite being identified as Theta II engine defect
Engine catastrophic failure—rod knock leading to blown engine
Owner reported rod knock beginning 05/22/21, engine failed/blew 05/27/21 when rod went through the block. Parts were on order but vehicle sat for over 2.5 weeks without repair update or loaner car after towing to dealership 05/28/21.
When: At approximately 105,000 miles (complaint #6); rod knock reported week before catastrophic failure
Symptoms owners cite: Rod knock noise preceding failure; Complete engine failure with rod piercing block
Repairs/costs cited: Engine blown; required full repair. Owner waited 2.5+ weeks with no status update; no loaner vehicle provided. Owner reported job loss due to vehicle unavailability.
Recalls/TSBs owners mention: Stated parts were ordered; no proactive support or timeline given
Transmission stuck in gear / transmission cable slippage
In two separate incidents, transmission became stuck either in reverse or park. One owner diagnosed transmission cable slipped off; another had unknown part near gearshift disconnected. Both required towing.
When: Complaint #8 at 45,162 miles; Complaint #2 at 119,000 miles
Symptoms owners cite: Transmission stuck in reverse; Transmission stuck in park; Gear shifter stuck or seized
Repairs/costs cited: Complaint #8: transmission cable slipped off, required repair (status unclear). Complaint #2: unknown part near gearshift was disconnected and repaired at independent mechanic.
Shift lock failure—park disengages without brake pedal pressure
Multiple owners report gear shifter easily moves out of park position without depressing the brake pedal, creating a safety hazard. One owner's vehicle rolled from park into the street with engine off and no key in ignition, nearly causing a collision.
When: Complaint #1 at 69,000 miles; Complaint #3 occurred with engine off and keys not in ignition; Complaint #7 at 90,000 miles
Symptoms owners cite: Gear shifter easily disengages from park without brake pressure; Vehicle rolls out of park unintended; Shift lock release must be manually engaged to shift out of park
Repairs/costs cited: Complaint #1: vehicle in process of being repaired at dealer. Complaint #3: Kia stated this was not a safety issue; owner paid out of pocket. Complaint #7: vehicle not repaired.
Recalls/TSBs owners mention: Complaint #1: VIN not included in NHTSA Campaign 17V773000 (service brakes); manufacturer did not assist. Complaint #3: Kia denied this was a safety issue. Complaint #7: Manufacturer notified but did not respond.
Brake light malfunction
Multiple owners report rear brake lights remaining illuminated at all times or failing to illuminate when brake pedal is depressed. One owner's brake light bulbs fractured immediately after replacement.
When: Complaint #1 at 69,000 miles; Complaint #2 at 119,000 miles; Complaint #7 at 90,000 miles
Symptoms owners cite: Rear brake lights stay on continuously without key in ignition; Brake lights fail to illuminate when brake pedal depressed; Brake light bulbs fracture immediately after replacement
Repairs/costs cited: Complaint #1: repair was in process. Complaint #2: bulbs replaced but immediately fractured; vehicle not repaired. Complaint #7: vehicle not repaired.
Traction control indicator illumination
Traction control light illuminates continuously while vehicle is stationary or driving at various speeds.
When: Complaint #7 at 90,000 miles
Symptoms owners cite: Traction control indicator illuminates continuously
Engine shutdown at highway speeds
Motor shuts down unexpectedly while driving at highway speed and flow of traffic.
When: Complaint #10; mileage not stated
Symptoms owners cite: Motor shuts down at high speed on freeway; Motor shuts down on highways
Display screen seizure
Infotainment display screen became unresponsive.
When: Complaint #2 at 119,000 miles
Symptoms owners cite: Display screen seized
Synthesized from 10 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 0 most recent
Had powertrain trouble with your 2012 Kia Forte?
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 2012 Kia Forte?
It's a documented issue but not catastrophic. 10 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?
Across the 8 complaints that reported odometer mileage, most powertrain failures cluster between 75,000 and 100,000 miles, with the median around 80,000. A quarter of owners report trouble before 75,000; a quarter make it past 100,000. 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/2012/Kia/Forte.
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.