This preliminary informational (PI) bulletin provides information to dealership personnel that may be helpful when addressing underbody component corrosion with customers.
full bulletin at NHTSA ↗2015 Chevrolet Colorado powertrain problems
severe Owners of the 2015 Chevrolet Colorado have filed 40 NHTSA complaints about the powertrain, typically surfacing around 17,900 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
40
Recalls
0
Avg fix
$2,500
| Model year | powertrain complaints |
|---|---|
| 2015 Colorado (this page) | 40 |
| 2016 Colorado | 83 |
| 2017 Colorado | 100 |
| 2018 Colorado | 76 |
| 2019 Colorado | 60 |
2crashes
3injuries
When does it fail?
Of the 40 powertrain complaints filed for the 2015 Chevrolet Colorado, here's the actual mileage breakdown — failures cluster heaviest at 25,000-50,000 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
Owners have filed 40 powertrain complaints with NHTSA against this vehicle, but no formal recall covers the issue — the federal record reflects what manufacturers have admitted, not everything owners are reporting.
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.
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 Preliminary Information communication provides information to the technician about vehicles that may have a delayed engagement into drive, shudder at a launch, or the transmission is slipping when shifting into 1st, 2nd, 3rd or 4th gears. This may be due to loose stator support to pump cover bolts causing a leak at the stator support to pump cover gasket. Technician will check for the bolts to be loose. If any of the bolts are loose or the gasket is misaligned or leaking, the transmission pump cover must be replaced and the 1234 clutch plates should be inspected for being distressed and repaired as needed.
full bulletin at NHTSA ↗This bulletin provides information on identifying Non-GM Engine Calibrations for Gasoline Engines using the Tech 2 or GDS 2.
full bulletin at NHTSA ↗This service bulletin provides information on the harmful effects of ethylene glycol in transmission fluid.
full bulletin at NHTSA ↗This informational bulletin explains Unscheduled Supplemental Services and the importance of GM Simplified Maintenance Schedules.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
The biggest complaint across these 40 narratives is transmission behavior: the 6-speed automatic fails to downshift promptly when you press the throttle, forcing the engine to lug and buck. Drivers report having to mash the pedal to force a downshift, then the truck lurches forward suddenly—a pattern that repeats constantly in stop-and-go traffic and highway driving. Many owners say this happens from day one and persists past 15,000 miles despite dealers resetting the control module. GM repeatedly told owners the transmission was "learning" their driving style or had been "designed" for fuel economy and would not repair it.
Owners also report transmission slipping between gears (especially 3rd-4th), spark knock during acceleration, and the transmission hunting for the right gear while driving steady speed. One owner experienced unintended acceleration in reverse that caused a multi-vehicle collision. Another encountered violent highway vibration at 24,000 miles; the dealership spent 40 days replacing suspension parts, tires, wheels, and the rear differential but never solved it.
Additional complaints include engine hesitation on takeoff that nearly causes stalls at intersections, power steering failure at 96,000 miles (despite a recall repair), brake squeal, and intermittent ABS/StabiliTrak warning lights. One owner reported an ignition key stuck in the switch. Dealers consistently told owners the behavior was "normal" or "functioning as designed," and GM assigned engineers to some cases but provided no fixes. The 2017 Colorado received a different 8-speed transmission—a tacit admission the original powertrain had a design problem.
Same Chevrolet Colorado powertrain reports on nearby years: 2016 · 2017 · 2018
Failure modes owners describe
Transmission hesitation and delayed downshift on acceleration
The 6-speed automatic transmission fails to downshift promptly when throttle is applied at low speeds or during moderate-speed driving, causing the engine to lug and buck. Engine RPM sits too low for the load, requiring drivers to push the pedal harder to force a downshift. Once downshift occurs, it is often abrupt, causing sudden acceleration that creates traffic hazards.
When: Onset within first 200–15,000 miles; reported as persistent from purchase or shortly after
Symptoms owners cite: Engine lugging and bucking at low throttle input; Delayed acceleration response; Delayed or missed downshift when accelerator pressed; Abrupt multi-gear downshift when full throttle applied; Hesitation that mimics near-stall condition
Repairs/costs cited: Dealers performed transmission control module resets and software updates; GM claimed issue was transmission 'learning' driving style or designed for fuel economy; no permanent repair identified in complaints
Recalls/TSBs owners mention: GM told owners the transmission was 'learning' driving style and would improve; some dealers reset ECM/control module; dealerships repeatedly stated behavior was 'normal' or 'designed into the vehicle'; GM engineers were aware per one complaint but offered no fix; 2017 Colorado received different 8-speed transmission
Transmission slipping between gears
Transmission slips out of gear momentarily or fails to fully engage, particularly between 3rd and 4th gears. Slippage takes 2–3 seconds to resolve, with engine revving up before transmission finally pops into gear. Occurs on relatively low-mileage vehicles.
When: Under 40,000 miles; one case at 83,000 miles
Symptoms owners cite: Transmission slips between 3rd and 4th gear; Delay of 2–3 seconds before engaging; Engine revs without load before re-engagement; Occasional slip between 4th and 5th gear
Repairs/costs cited: Dealers recommended ensuring transmission fluid is warmed up before driving; no permanent repair documented
Recalls/TSBs owners mention: GM classified slipping behavior as 'normal' and refused repair
Transmission hunting and incorrect gear selection
Transmission repeatedly searches for the correct gear, failing to stay in a single gear at steady speed. Vehicle bucking, shuddering, and jerking result from the transmission cycling through multiple gears as if confused about proper selection.
When: Present from early ownership; reported at 11,000–15,000 miles and beyond
Symptoms owners cite: Transmission hunts for gears while driving steady speed; Vehicle bucks and shudders; Jerking and chattering sensation; Transmission appears to be in wrong gear for speed/load
Repairs/costs cited: No repairs documented; dealers attributed to 'learning' transmission behavior
Recalls/TSBs owners mention: Dealers stated transmission was in 'learning mode' and would improve; no remedial action offered
Spark knock (detonation) during acceleration
Engine produces audible spark knock or pinging during upshift and under moderate acceleration. Occurs across all gears. Indicates engine running too lean or timing advancing too far for octane rating or load.
When: From 17,000 miles onward; present since new
Symptoms owners cite: Audible spark knock/pinging during upshifts; Spark knock during acceleration; Knock present across all gears
Repairs/costs cited: No repair noted
Recalls/TSBs owners mention: Dealership acknowledged issue but offered no fix; complaints note GM engineers were aware
Unintended acceleration and loss of vehicle control
Vehicle accelerated unexpectedly in reverse and forward during low-speed maneuvering, causing collision with parked vehicles and curb. Driver unable to shift out of gear or disable power during event. Represents potential loss of control hazard.
When: At approximately 27,000 miles
Symptoms owners cite: Unintended backward acceleration; Unintended forward acceleration after reverse motion; Driver unable to shift out of gear; Driver unable to power down vehicle
Repairs/costs cited: Vehicle was towed to collision center; transmission failure suspected by owner but not verified
Recalls/TSBs owners mention: No manufacturer contact; incident handled by insurance
Transmission jerking uphill and jumping in/out of gear
While driving uphill, transmission jerks vehicle forward involuntarily and jumps in and out of gear without driver input. Causes sudden acceleration and neck injury from violent jerking.
When: At approximately 28,000 miles
Symptoms owners cite: Vehicle jerks forward independently; Transmission jumps in and out of gear; Sudden unexpected acceleration
Repairs/costs cited: No failure codes generated; dealer unable to determine cause and stated vehicle could not be repaired
Recalls/TSBs owners mention: Manufacturer notified; assigned investigator but could not duplicate failure; no remedy provided
Engine hesitation and near-stall on takeoff
Vehicle hesitates or nearly stalls when accelerating from a stop or very low speed, particularly at intersections or in stop-and-go traffic. Engine and transmission appear to struggle to engage. Requires full-pedal input to prevent stall.
When: From purchase onward; reported at 6,000–18,000 miles
Symptoms owners cite: Hesitation from stop; Near-stall sensation on acceleration; Limited acceleration until full throttle applied; Jerking motion during takeoff
Repairs/costs cited: Transmission service performed in one case; stalling occurred after; no root cause repair documented
Recalls/TSBs owners mention: Dealers stated hesitation was 'normal' and vehicle 'functioned as intended'; referred customer to NHTSA hotline; no remedy offered
Violent highway vibration at speed
Severe vibration that shakes the entire vehicle at highway speed (80 MPH), persisting despite extensive dealer service including suspension work, tire replacement, wheel replacement, and rear differential rebuild and replacement. Dealer and manufacturer cannot identify root cause.
When: At approximately 24,000–25,000 miles while driving on Interstate 10
Symptoms owners cite: Violent shaking and vibration at highway speed; Entire truck shakes as if coming apart; Vibration present after tire and wheel replacement
Repairs/costs cited: Dealership service over 40 days: replaced upper right control arm, road-force balanced tires twice, performed alignment twice, replaced tires, replaced tires/wheels with 2017 Colorado parts, rebuilt rear differential, replaced rear differential with factory unit—problem unresolved
Recalls/TSBs owners mention: GM elevated concern to engineering; worked with dealer but could not identify root cause or provide timeline for fix; acknowledged safety concern but no recall issued
Power steering loss
Power steering unit suddenly fails while driving at moderate speed, resulting in loss of power steering assistance and difficult manual steering. Vehicle loses electrical assist.
When: At approximately 96,000 miles
Symptoms owners cite: Loss of power steering functionality; Difficult manual steering; Power steering unit internal failure
Repairs/costs cited: Independent mechanic diagnosed power steering unit failure requiring replacement; vehicle not repaired by owner
Recalls/TSBs owners mention: Recall for power steering unit issued in 2016; despite recall repair, failure recurred
Brake squeal and transmission noise during gear search
Brakes produce loud squealing at low speeds both forward and in reverse. Transmission makes rattling/pinging noise when hunting for correct gear, particularly during acceleration.
When: At 11,000 miles
Symptoms owners cite: Brake squeal at low speeds; Squeal in forward and reverse; Rattling/pinging noise during gear hunting; Noise occurs during slow, fast, uphill driving and acceleration
Repairs/costs cited: No repair documented
Recalls/TSBs owners mention: No response documented
Stability control and ABS warning lights intermittent
ABS, traction control, and StabiliTrak warning lights illuminate and turn off intermittently while driving. Dealership initially stated lights indicated no issue; owner reported recall existed for certain regions.
When: Mileage not specified; vehicle in use on road
Symptoms owners cite: ABS warning light cycles on/off; Traction control light cycles on/off; StabiliTrak light cycles on/off
Repairs/costs cited: No repair documented
Recalls/TSBs owners mention: Partial recall for certain regions; no fix for complainant's area
Ignition key sticking in switch
Ignition key becomes stuck and cannot rotate fully to shut off engine or be removed from switch. Requires jiggling or repositioning shift lever to extract key. Limits vehicle shutdown ability.
When: At 15,000 miles; also reported as common on 2015–2016 models per forums
Symptoms owners cite: Key stuck in ignition; Key cannot rotate to off position; Key cannot be removed without repositioning shift lever
Repairs/costs cited: One dealership repair documented: transmission control lever knob was not fully seated and was adjusted
Recalls/TSBs owners mention: No formal manufacturer response documented
Synthesized from 40 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 2 most recent
The transmission is slipping between 3rd and 4th gear. Takes a few seconds to actually get into gear. When brought back to the dealership they were able to replica the problem. When it was brought up to be repaired with gm they reported the issue as normal and to make sure the transmission fluid is warmed up prior to drive. Although it still slipping on a truck under 40k miles. They are…
Purchased 2015 colorado july 2015.we had it in for oil changes & a few times regarding hesitation of acceleration. Service techs did not type complaint when in for oil change only when brought in specifically for acceleration issue. They stated it was our fault we did not read the work order.it is not my job to read a work order it's the service techs job to enter every complaint or issue…
Had powertrain trouble with your 2015 Chevrolet Colorado?
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 2015 Chevrolet Colorado?
It's a meaningful issue. 40 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 24 complaints that reported odometer mileage, most powertrain failures cluster between 6,356 and 38,000 miles, with the median around 17,900. A quarter of owners report trouble before 6,356; a quarter make it past 38,000. 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/2015/Chevrolet/Colorado.
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.