GM is receiving damaged (cracked or broken) transmission cores returned to the reman facilities. The damage is being caused either in the removal process by the technician, or inadequate packaging or shipping. This bulletin advises the dealers to be more careful not to damage the transmissions during removal and to package the core properly for return.
full bulletin at NHTSA ↗2006 Chevrolet HHR powertrain problems
moderate 65 complaints filed with NHTSA · avg repair $2,500 · see powertrain across all vehicles →
Failure mileage
Complaints
65
Recalls
0
Avg fix
$2,500
2crashes
When does it fail?
Of the 65 powertrain complaints filed for the 2006 Chevrolet HHR, 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
Of the 6 model years of Chevrolet HHR we track for powertrain problems, this one carries the most owner complaints on file — 65.
Owners have filed 65 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.
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 Warranty Admin service bulletin provides guidelines for Dealers Not Required and for Dealers Required to Contact the PQC for engine or transmission assembly replacement and explains the PQC process, GWM Transaction submission, vehicle service record retention and proper handling of assembly returns for Canadian Dealers only.
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 service bulletin provides a vibration analysis worksheet the technician can use in conjunction with the appropriate Vibration Analysis-Road testing procedure when diagnosing vibration concerns.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
The 2006 HHR powertrain complaints center on a defective shifter interlock mechanism that fails regularly across all mileage levels. Owners report the key stuck in the ignition because a metal pin in the gear shifter assembly works loose or breaks out of its plastic bracket, preventing the transmission lock microswitch from engaging. The shifter button gets stuck depressed, and the vehicle won't power down—battery drains completely within hours. Chevrolet denies this is a known defect and won't recall pre-2009 models, even though independent mechanics and dealers confirm they've seen dozens of these repairs.
Equally serious: the transmission fails to lock in Park or shifts between gears without the brake pedal pressed. Vehicles roll away on inclines, and drivers can't keep them in Park even with the key inserted. Some transmissions lose forward motion entirely at highway speeds, leaving owners stranded. Hard shifting and jerking during acceleration are widespread, particularly when the fuel tank runs low.
The PCM (engine computer) can fail suddenly, triggering "Engine Disabled" messages and stalling the vehicle while driving. Clutch master cylinders break free from the firewall, rendering the clutch inoperable. Transmission seals leak at low mileage, and electrical connectors on the transmission harness fail from strain caused by poor routing.
Owners routinely pay $200–$600 out of pocket for repairs dealers say aren't covered, while GM sits behind warranty disclaimers. Service bulletins exist, but recalls don't—a disconnect that leaves owners frustrated and at genuine safety risk.
Same Chevrolet HHR powertrain reports on nearby years: 2007 · 2008 · 2009
Failure modes owners describe
Shifter Interlock / Key Removal Failure
Metal pin in gear shifter assembly works loose or falls out of plastic retainer bracket. This prevents the transmission interlock microswitch from engaging, making the key impossible to remove from the ignition even when vehicle is in Park. Some owners report the shifter button sticks in depressed position. Owners cite a plastic piece cracking around the pin hole; GM later reinforced the replacement part with metal. Dealer networks acknowledge seeing many of these; some dealers mention redesigned shifters but frame as warranty work only.
When: Variable mileage and age; reports from 11,000 to 147,000 miles; occurs from early life to late in vehicle lifespan. Often recurs after attempted repairs.
Symptoms owners cite: Key will not turn to removal detent position in ignition; Key stuck/seized in ignition cylinder; Shifter button stuck in depressed inward position; Must manipulate gear shifter repeatedly to release key; Radio and other electrical systems remain on when key cannot be removed; Battery drains because vehicle cannot be fully powered off
Repairs/costs cited: Replacement part #25864102 (shifter assembly); dealers quote $150–$600+ labor and parts combined. Some owners pay $215–$250 for shifter replacement alone. GM upgraded replacement with metal-reinforced plastic. Dealers in low-population areas report seeing 6–7 cases in 12 months.
Recalls/TSBs owners mention: Chevrolet denies knowledge of defect; claims no recall issued for 2006–2008 models despite service bulletin existence. Recalls issued for 2009+ and Cobalt models only. EPA-mandated warranty used in at least one case (PCM failure, narrative #1). GM regional service bulletin 06-07-30-004F mentioned by one owner.
Shifter Mechanism / Park Engagement Failure
Gear selector does not lock solidly into Park position or allows shifting between gears without depressing brake pedal or shift button. Vehicle can roll or shift gears unprompted, especially with key out or engine off. Shifter moves freely from Park to Reverse, Neutral, or Drive with only a light bump or pressure. Can occur with or without key in ignition, and some vehicles will start without being in Park.
When: Reports from 31,000 to 144,000 miles; some early failures noted. Issues persist or recur after repair attempts.
Symptoms owners cite: Shifter does not lock in Park; moves freely between gears; Vehicle rolls away or shifts out of Park on inclines or slight impacts; Gears can be changed without depressing brake or shift latch button; Vehicle shifted from Park to Reverse while parked, causing rollaway into another vehicle or objects; Gear indicator shows Park but transmission is actually in Reverse or Neutral; Vehicle will not start because selector not properly in Park; Cannot shift out of Park even after waiting and multiple attempts
Repairs/costs cited: Shifter assembly replacement; transmission shift cable adjustment; in one case transmission cable adjustment clip dislodged. Dealer costs $150–$300+ parts plus labor. Some owners attempted transmission flush without success.
Recalls/TSBs owners mention: Dealers claim no TSB or recall for 2006 models. Recall 09V073000 issued but limited to certain years/VINs, leaving earlier models uncovered. One owner cites GM TSB #06-07-30-004F.
Transmission Failure (Complete Loss of Drive)
Transmission suddenly loses ability to propel vehicle forward, though may still shift gears, move in Reverse, or rev engine. In one case, transmission failed on a hill; in another, at 55,000 miles despite extended warranty. One narrative reports transmission would not shift from 1st to 2nd or 3rd to 4th gear, remaining stuck in 2nd.
When: Reported at 55,000 miles (with extended warranty), on highway at varying speeds. One case at approximately 7,800 miles.
Symptoms owners cite: No forward motion when accelerating despite engine revving; Vehicle will move in Reverse but not Forward; Grinding or hard shifting sensations before total failure; Transmission will not shift out of particular gear or between certain gear pairs; Vehicle stalls or loses power during acceleration
Repairs/costs cited: Transmission replacement quoted at $1,500 difference for new transmission versus $0 for used unit with 33,000 miles already on it (both covered under extended warranty). One case involved internal transmission problems and bad electrical connectors diagnosed by independent mechanic.
Recalls/TSBs owners mention: Dealer could not determine root cause of failure. Extended warranty covered replacement but required cost difference for new vs. used. One owner with extended warranty faced confusing repair options and delay (two weeks to diagnose).
Hard Shifting / Transmission Jerking
Transmission shifts harshly or jerks during gear changes, especially during acceleration from stop or at speed. May occur intermittently (25% of the time per one owner) but recurs unpredictably. Check Engine and Traction Control lights often illuminate. Problem sometimes appears after fuel is refilled and fuel injector cleaner added, or after transmission fluid flush.
When: Reported at 60,000 miles, 92,000 miles, and higher; some owners note issue after vehicle parked on empty fuel tank.
Symptoms owners cite: Hard jerking motion during acceleration or gear shifting; Transmission jerks when starting from stopped position; Check Engine light illuminates; Traction Control light comes on; Jerking particularly noticeable when gas tank nearly empty; Problem resolves temporarily after fuel refill and injector cleaner; Remote start fails when Check Engine light is on
Codes mentioned: Check Engine codes (not specified in detail)
Repairs/costs cited: Transmission fluid flush performed without resolving issue. One owner added fuel injector cleaner with temporary improvement. No permanent repair mentioned in narratives.
Recalls/TSBs owners mention: No manufacturer response documented for hard-shifting complaints.
PCM / Engine Control Computer Failure
Powertrain Control Module (PCM) develops memory error, causing vehicle to shut down while driving. Driver Information Center displays 'REDUCED ENGINE POWER' then 'ENGINE DISABLED,' after which engine stalls immediately. Vehicle may not restart for several minutes. Check Engine light indicates PCM MEMORY ERROR (code unfamiliar to independent service station). Chevrolet dealership determined PCM needed replacement.
When: Reported at unspecified mileage in 2008; vehicle 2006 model year.
Symptoms owners cite: DIC display flashes 'REDUCED ENGINE POWER'; DIC display then shows 'ENGINE DISABLED'; Engine shuts down immediately while driving at 25–30 mph; Vehicle will not restart immediately; requires waiting several minutes; Check Engine light turns on; Vehicle stalls after restart and short drive (within few yards)
Codes mentioned: PCM MEMORY ERROR
Repairs/costs cited: PCM replacement performed at Chevrolet dealership under EPA-mandated warranty (powertrain warranty coverage).
Recalls/TSBs owners mention: Chevrolet customer support stated owner should have no complaint because repair was free under EPA-mandated warranty. No acknowledgment of safety concern that the failure mode posed (sudden stall in traffic).
Ignition Switch / Key Removal Mechanical Failure
Key difficult or impossible to turn to the OFF/LOCK position and cannot be removed from ignition cylinder. Often linked to shifter interlock issues but sometimes a separate ignition mechanism problem. Owner reported key seized in ignition; dealer replaced ignition switch cylinder.
When: Reported at 132,441 miles; other cases unspecified.
Symptoms owners cite: Key cannot turn to final detent (OFF/LOCK) position; Key cannot be removed from ignition; Key seized in ignition cylinder; Engine cannot be fully shut off
Repairs/costs cited: Ignition switch cylinder replacement; in one case also included battery replacement. One owner reports having to access manual release button under steering column.
Recalls/TSBs owners mention: No response documented.
Transmission Connector / Electrical Failure
Transmission electrical connector harness is too short, causing strain on the connector plug when drivetrain flexes. Connector pins fail, leading to internal transmission error codes and poor electrical connection.
When: Timing not specified; related to electrical diagnostics.
Symptoms owners cite: Check Engine / Repair light illuminated; Diagnostic codes indicating internal transmission problems; Diagnostic codes for bad connections in electrical system
Codes mentioned: Internal transmission fault codes, Electrical system connection faults
Repairs/costs cited: Problem localized to connector plug on transmission; harness wire too short resulting in strain and pin failure.
Recalls/TSBs owners mention: No response documented.
Transmission Seal Leak
Transmission output seal fails early in vehicle life, causing fluid leak. Accompanied by noise on acceleration after seal replacement, which dealer initially misdiagnosed as catalytic converter issue.
When: At 5,000 miles; noise continued through 14,500 miles.
Symptoms owners cite: Transmission fluid leaking from seal; Noise when accelerating after seal repair; Ongoing noise unresolved after multiple dealer visits and catalytic converter replacement
Repairs/costs cited: Transmission seal replaced; catalytic converter replaced but was not the source of noise. Manufacturer rep claimed noise was normal.
Recalls/TSBs owners mention: Manufacturer rep stated noise was usual/normal. Second opinion from manufacturer still pending per narrative.
Clutch Master Cylinder Failure
Clutch master cylinder breaks out of the firewall, rendering the clutch inoperable. Clutch pedal goes to floor with popping noise, leaving driver stranded mid-roadway. Mechanic noted reports of similar issues in other Chevrolet products.
When: Timing during normal operation at stopped position in turn lane.
Symptoms owners cite: Popping noise from clutch pedal; Clutch pedal goes to floor; Vehicle becomes inoperable (cannot shift or move)
Repairs/costs cited: Clutch master cylinder broken/separated from firewall; mechanic repaired without pulling engine.
Recalls/TSBs owners mention: Dealer had no knowledge of the problem. Mechanic discovered reports of similar issues in other Chevy products.
Shifter Knob Detachment
Top section of the gear shifter knob suddenly detaches while vehicle is in motion during gear shift operation. Knob is injection-molded plastic construction.
When: At 52,900 miles; incident occurred while shifting from 3rd to 4th gear during acceleration.
Symptoms owners cite: Shifter knob detaches while driving; Driver must grab middle part of shifter to continue operation
Repairs/costs cited: Knob detachment only; shifter remained functional without knob.
Recalls/TSBs owners mention: No response documented. Owner believed recall should be issued.
Multiple Cascading Powertrain / Electrical Failures
Vehicle exhibits multiple, cascading failures over time including computer failure, shifter malfunction, power steering failure, and inability to start. After one repair (power steering replacement with used unit and reprogramming), vehicle becomes locked and will not crank. Owner reports difficulty steering and nearly crashing multiple times.
When: Over an extended period; owner attempting repairs for 2+ months.
Symptoms owners cite: Computer failure; Gear shift failure; Power steering failure / extreme difficulty steering; Engine will not start / crank; Vehicle locks and cannot be started after power steering repair attempt; Multiple near-crash incidents due to steering difficulty
Repairs/costs cited: GM replaced computer under warranty; owner paid for gear shift repair; owner attempted power steering replacement with used unit and reprogramming, which then caused vehicle to lock and not start. Dealer claims out-of-warranty issues.
Recalls/TSBs owners mention: GM stated over-mileage, claims owner should have had all warranties though dealer went out of business.
Synthesized from 65 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 1 most recent
Tl*the contact owns a 2006 Chevrolet hhr. The gear mechanism failed. He has attempted to place the gear position indicator in the park position and the engine will not shut off. This failure can cause the vehicle to shift out of gear on its on with or without the driver present. The dealer stated that it was a common problem. The current and failure mileages were 39000.****
Had powertrain trouble with your 2006 Chevrolet HHR?
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 2006 Chevrolet HHR?
It's a documented issue but not catastrophic. 65 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 59 complaints that reported odometer mileage, most powertrain failures cluster between 40,000 and 97,000 miles, with the median around 60,000. A quarter of owners report trouble before 40,000; a quarter make it past 97,000. 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/2006/Chevrolet/HHR.
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.