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 ↗2008 Chevrolet HHR powertrain problems
moderate 14 complaints filed with NHTSA · avg repair $2,500 · see powertrain across all vehicles →
Failure mileage
Complaints
14
Recalls
0
Avg fix
$2,500
When does it fail?
Of the 14 powertrain complaints filed for the 2008 Chevrolet HHR, 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 16 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.
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 ↗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 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 ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
Owners report widespread powertrain troubles on the 2008 HHR. The automatic transmission fails prematurely, requiring rebuild before 100,000 miles—it starts with over-revving on upshifts and progresses to severe drag, all without throwing a check engine light. Chevrolet has refused to acknowledge the pattern despite similar failures in Cobalts and Malibus using the same unit. Manual transmission clutches stick to the floor, leaving the pedal fully engaged and forcing owners to manually pull it up. The shift knob itself can separate and fall under the brake pedal mid-drive.
Electrical gremlins plague early examples: batteries drain relentlessly (one owner replaced four in short order), engines stall mid-drive without warning, and audio systems drop out. Brake failure—pedal sinking to the floor—appears hand-in-hand with the electrical chaos. Cold weather can trap the shift selector in Park. One vehicle at 27,000 miles suffered a punctured transfer case from road debris because the protective shield was missing from the factory.
Fuel and brake lines rust through in the left rear area due to poor shielding design that traps salt and moisture. A traction control malfunction caused loss of power and acceleration at highway speed, and dealer visits proved fruitless. Overall, these are not isolated quirks—they repeat across multiple units and model years.
Same Chevrolet HHR powertrain reports on nearby years: 2006 · 2007 · 2009 · 2010
Failure modes owners describe
Automatic Transmission Failure / Rebuild
Transmission requires rebuild or replacement well under 100,000 miles. Begins with over-revving during gear shifts from 1st-to-2nd and 2nd-to-3rd, followed by severe drag as if driving with high resistance. No check engine light present. Affects Chevrolet Cobalt, HHR, and Malibu models with same transmission.
When: 98,778 miles reported; another at 104,124 miles
Symptoms owners cite: Over-revving when shifting 1st-to-2nd and 2nd-to-3rd; Severe drag sensation despite normal throttle input; No check engine light illuminating; Transmission fails to respond normally to shifts
Repairs/costs cited: Dealer recommended flush and filter; transmission shop performed full rebuild at owner's expense; repairs rejected by Chevy on warranty
Recalls/TSBs owners mention: Chevrolet refuses to acknowledge problem despite widespread owner reports
Manual Transmission Clutch Master Cylinder Failure
Clutch master cylinder fails, causing loss of clutch engagement and vehicle unable to accelerate when pedal is pressed. Occurs on manual transmission models.
When: 118,000 miles
Symptoms owners cite: Clutch pedal depressed but vehicle fails to accelerate; Loss of clutch engagement
Repairs/costs cited: Independent mechanic diagnosed clutch master cylinder replacement needed; part no longer manufactured by Chevy
Recalls/TSBs owners mention: Manufacturer stated part no longer manufactured
Manual Transmission Clutch Pedal Sticks to Floor
Clutch pedal becomes sticky, then sticks completely to floorboard, leaving clutch fully engaged. Pedal must be manually pulled up when vehicle is off to function again. Often coincides with grinding reverse gear and inability to shift into gears.
When: Reported as ongoing issue on multiple vehicles
Symptoms owners cite: Clutch pedal feels squishy initially; Pedal sticks to floorboard when engaged; Reverse gear grinds and will not engage; Difficulty shifting into gears; Driveline noise and severe rattling sounds ('can rolling down a hill')
Repairs/costs cited: No specific repairs cited in narratives
Transmission Shift Interlock / Ignition Lock Failure
Transmission becomes stuck in Park and cannot be shifted; ignition key becomes stuck in Accessory mode and cannot be removed. Vehicle will not start after cycling ignition, even though recall for ignition switch had been previously completed.
When: January 2015 reported
Symptoms owners cite: Transmission will not shift out of Park; Ignition key stuck in Accessory mode; Key cannot be removed from ignition; Vehicle will not start after key stuck; Audio system dropout reported prior to failure
Repairs/costs cited: No repair completed; vehicle required tow home
Recalls/TSBs owners mention: Ignition switch recall had been performed, but failure still occurred
Electrical System Battery Drain
Vehicle electrical system drains battery repeatedly, requiring multiple battery replacements in short timeframe. Draining is severe and chronic, lasting from purchase through multiple service attempts. Vehicle stalls while driving and fails to start during wet weather.
When: Within weeks of purchase in June 2008; ongoing through complaint date
Symptoms owners cite: Rapid battery drain; Engine stalling while driving on road; Failure to start in heavy rain; Vehicle brought to shop 17 times for electrical issues; Four batteries required in short ownership period
Repairs/costs cited: Dealership unable or unwilling to diagnose; no repairs completed despite multiple visits
Recalls/TSBs owners mention: GM offered 10% discount but refused lemon buyback (vehicle was used); GM stated 2007 model had same issue but refused to address
Engine Stalling During Operation
Engine stalls unexpectedly while driving, creating hazard. Audio system also reported dropping out. Occurs multiple times on same vehicle.
When: Multiple instances on early 2008 model
Symptoms owners cite: Engine stalls while driving on road; Audio system dropout (5 minutes in one case); Electrical system failure preventing hazard lights from functioning
Repairs/costs cited: No specific repairs documented
Brake System Failure
Brake pedal loses pressure and sinks to floor, causing loss of braking at stop sign. Represents immediate safety hazard.
When: Ongoing from June 2008 purchase
Symptoms owners cite: Brake pedal goes to floor; Loss of braking ability at stop
Transfer Case / Transmission Fluid Leak
Transfer case punctured by road debris, causing fluid loss and crash risk. Dealership found that protective shield was missing, allowing debris to penetrate case.
When: 27,031 miles
Symptoms owners cite: Fluid loss from punctured transfer case; Increased crash risk from loss of drivetrain function
Repairs/costs cited: Transmission, gasket, and transmission fluid replaced at dealership
Recalls/TSBs owners mention: Shield was missing as manufactured
Fuel Line Rust-Through and Brake Line Corrosion
Metal fuel line rusted through at left rear tire area and leaked fuel. Purge line also corroded and broke. Lines run through a tubular knitted heat shield that collects dirt, salt, and moisture, promoting rust. Design allows salt and debris to accumulate in shield.
When: At undisclosed mileage
Symptoms owners cite: Fuel line leak at left rear tire; Rust-through of metal fuel line; Purge line corroded and broken; Brake line corrosion in same area
Repairs/costs cited: Owner purchased and installed aftermarket fuel line kit
Manual Shift Knob Separation
Top half of manual transmission shift knob separates and falls into vehicle cabin during normal shifting. Creates hazard by falling under brake pedal.
When: Two separate incidents reported
Symptoms owners cite: Top half of shift knob detaches during shifting; Knob falls to driver side floor; Knob falls under brake pedal
Repairs/costs cited: No repairs cited
Recalls/TSBs owners mention: Dealer reported same problem occurring with other customer vehicles
Cold Start Gear Shift Interlock
Gear shift becomes stuck in Park when weather is cold, preventing vehicle from being driven. Problem persists even after repair attempt.
When: Ongoing since 2010
Symptoms owners cite: Cannot remove gear shift from Park in cold conditions; Shift interlock fails to release
Repairs/costs cited: Issue was addressed once but recurred
Traction Control Light and Acceleration Loss
While driving at moderate speed, vehicle loses acceleration power despite throttle input, coinciding with traction control warning light illumination. Dealer attempted multiple repairs including fuse box, wiring, and transmission replacement without resolving issue.
When: Failure at 55,000 miles; complaint filed at 83,000 miles
Symptoms owners cite: Loss of acceleration despite depressed accelerator; Traction control warning light illuminates; Vehicle speed decreases unintentionally
Repairs/costs cited: Dealer identified fuse box, wiring housing, and transmission as needing replacement; repairs not completed
Synthesized from 14 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 1 most recent
2008 Chevy hhr, stall 5 times, electrical system failed, no hazard light to warned other drivers of vehicle present. *tr
Had powertrain trouble with your 2008 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 2008 Chevrolet HHR?
It's a documented issue but not catastrophic. 14 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 12 complaints that reported odometer mileage, most powertrain failures cluster between 23,000 and 103,948 miles, with the median around 27,031. A quarter of owners report trouble before 23,000; a quarter make it past 103,948. 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/2008/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.