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 GMC Yukon powertrain problems
severe 17 complaints filed with NHTSA · avg repair $2,500 · see powertrain across all vehicles →
Failure mileage
Complaints
17
Recalls
0
Avg fix
$2,500
2fires
2injuries
When does it fail?
Of the 17 powertrain complaints filed for the 2008 GMC Yukon, here's the actual mileage breakdown — failures cluster heaviest at 100,000-125,000 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 8 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 of 2008 GMC Yukon models report a cluster of powertrain and electrical failures. Several report vehicles rolling away while parked in gear with the parking brake engaged, causing serious injury in one case. Multiple owners describe transmission problems including delayed gear engagement, harsh downshifts, lunging forward, inability to accelerate during merging, and complete transmission failure requiring replacement—all creating dangerous highway situations.
Hybrid-specific failures are prominent: stalling during autostop-to-engine transitions, loss of power and brakes while driving, engine cutouts at stops, and difficulty restarting. Owners report repeated visits to multiple dealerships with no resolution and claims of "normal operation" when the issue is clearly not.
Electrical issues appear widespread: complete power loss at highway speeds (loss of steering, brakes, gauges, hazard lights), intermittent door locks and window failures, parasitic battery drain, erratic warning lights, and in at least two cases, fuse box fires. One owner reports a failed u-joint on the driveshaft at 65+ mph, losing the yoke assembly. A transmission display readability issue under sunlight is also noted. Dealers frequently cannot duplicate problems or find codes, and GM has declined to issue recalls or warranties on several vehicles.
Same GMC Yukon powertrain reports on nearby years: 2007 · 2011
Failure modes owners describe
Parking brake / transmission park engagement failure
Vehicle rolls away while parked and in gear with parking brake engaged. Owner reports it happened multiple times over 15-20 minute intervals.
When: 3 weeks prior to report in one case; multiple occurrences in short timeframe
Symptoms owners cite: Vehicle rolls away while in park with parking brake on; Occurs on flat ground and on slight inclines
Transmission seal failure and shifting problems
Transmission seals fail repeatedly; transmission hesitates or fails to engage gears during acceleration. Delayed engagement leads to hard downshifts and lurching.
When: Throughout ownership; recurs within one week of seal replacement in one case
Symptoms owners cite: Transmission kicks back upon acceleration; Vehicle accelerates without engaging gear (engine revs, no forward motion); Hard delayed gear engagement throwing occupants forward; Same issue recurs after dealer seal tightening repair
Repairs/costs cited: Two separate dealerships replaced transmission seals twice; seals were found loose and re-tightened, but problem persisted
Transmission gear selection malfunction during acceleration
Transmission selects incorrect gear ratios during highway merging and acceleration, creating inability to accelerate followed by harsh downshifting and uncontrolled lurching.
When: Occurs frequently at all speeds
Symptoms owners cite: Transmission selects too high a gear, no power to accelerate; Delayed downshift into too low a gear; Uncontrolled lurching forward at high speed; Happens repeatedly during merging into traffic
Recalls/TSBs owners mention: Dealer and manufacturer refused to repair, claiming 'normal operation'
Autostop-to-engine transition failure (hybrid models)
When autostop mode engages at stops, the transition back to engine power fails—engine does not restart or clutch does not fully engage, causing stalling at traffic lights and stop signs.
When: Throughout ownership; occurs at traffic lights and stop signs
Symptoms owners cite: Engine stalls when trying to pull out from autostop; Vehicle dies in intersection after autostop exit; Clutch does not fully engage on transition to engine power; Partial engagement leaves very little power to accelerate
Repairs/costs cited: Auxiliary fluid pump replaced in one case; service bulletin issued for chafed/shorted harness in another; vehicle remained out of commission 10 months
Complete electrical power loss while driving
Vehicle loses all electrical power while driving at highway speeds—gauges go dead, power steering lost, brakes lost, radio off, hazard lights non-functional, door locks inoperable. Power returns after 10-15 minutes.
When: Highway speeds (60-70 mph); occurred at least twice in one case
Symptoms owners cite: 100% power loss at highway speed; Vehicle heaves and lurches before failure; All gauges go dead; Power steering inoperable; Brake power lost; Airbag light flashing; Manual door unlock required
Recalls/TSBs owners mention: Dealer unable to duplicate or locate problem
Fuse box fire and electrical shorts
Fuse box catches fire; electrical system experiences faults causing power loss, lunging, and brake failure. Fires occurred both initially and during dealer repair.
When: 2008 and later; occurred multiple times on one vehicle from August 2008 onward
Symptoms owners cite: Fire in fuse box; Vehicle lunges forward at low speeds; Complete loss of brakes and power steering; Requires towing each occurrence
Recalls/TSBs owners mention: Dealer claims vehicle fixed and safe; manufacturer not addressing issue
Intermittent electrical gremlins—doors, windows, running boards
Electrical system exhibits sporadic failures: door locks inoperable, power windows don't work, running boards don't function. When power is lost, vehicle is completely dead; recovers after 15 minutes.
When: Intermittent; periods of complete loss lasting 15 minutes
Symptoms owners cite: Door locks non-functional; Power windows fail; Running boards don't deploy; Vehicle completely unresponsive for 15 minutes, then recovers; Vehicle cutting out while driving; Random warning lights flashing
Throttle position sensor / engine power reduced codes
Engine control module detects throttle position sensor faults (P2122, P2138, P2128 codes), triggering stabilitrac, reduced engine power, and engine control module warning lights. Vehicle limited to 10-15 mph.
When: At approximately 20,000 miles
Symptoms owners cite: Vehicle acceleration limited to 10-15 mph; StabiliTrac light illuminates; Engine Control Module warning light; Engine Power Reduced indicator lights
Codes mentioned: P2122, P2138, P2128
Repairs/costs cited: Battery replaced twice; battery cables replaced multiple times; failure not corrected
Recalls/TSBs owners mention: Manufacturer contacted (case number provided); manufacturer stated electrical failure; vehicle not repaired
Fuel control module and body control module failure
Fuel control and body control modules fail, causing stalling at highway speeds and triggering traction control and reduced engine power warnings.
When: At approximately 115,000 miles
Symptoms owners cite: Vehicle stalls while driving 60 mph; Traction control indicator illuminates; Reduced engine power indicator illuminates
Repairs/costs cited: Fuel pump replaced; failure recurred
Recalls/TSBs owners mention: Dealer stated no recall exists; manufacturer stated nothing could be done; vehicle not repaired
Driveshaft u-joint failure
Rear driveshaft u-joint fails at highway speeds, causing severe vibration and loss of driveshaft/yoke assembly. Owner notes potential for gas tank puncture and fire.
When: At highway speeds (65-74 mph range)
Symptoms owners cite: Severe vibration starting at 65 mph; Vibration increases through 74 mph range; Sound from passenger rear quarter area
Repairs/costs cited: Failed u-joint; yoke assembly and driveshaft lost; multiple dealers could not diagnose before failure
Transmission failure requiring replacement
Transmission fails completely and requires replacement. Vehicle unable to accelerate or respond to driver inputs.
When: At approximately 102,000 miles
Symptoms owners cite: Vehicle fails to accelerate at 30 mph; Vehicle must be pulled over and engine shut off; After restart, vehicle continues to malfunction
Repairs/costs cited: Transmission replacement needed
Recalls/TSBs owners mention: Manufacturer notified; vehicle not repaired
Transmission display readability in sunlight
Transmission gear indicator (P-R-N-D-3) and driver information center display are impossible to read under bright sunlight conditions.
When: Ongoing
Symptoms owners cite: Gear indicator not visible in bright sun; Driver information center not visible in bright sun
Transmission whining in reverse and first gear
Transmission produces loud whine when placed in reverse and first gear. Vehicle will not move unless shifted to manual M2 mode.
When: Ongoing
Symptoms owners cite: Loud whining noise in reverse; Loud whining noise in first gear; Vehicle will not move in normal reverse or first gear
Repairs/costs cited: Vehicle must be manually shifted to M2 to move
Synthesized from 17 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 2008 GMC yukon. While driving approximately 60 MPH, the vehicle stalled and the traction control and reduced engine power indicators illuminated. The vehicle was taken to an independent mechanic where it was diagnosed that the fuel control module and the body control module were faulty and needed to be replaced. The technician replaced the fuel pump, but the failure…
Had powertrain trouble with your 2008 GMC Yukon?
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 GMC Yukon?
It's a meaningful issue. 17 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 13 complaints that reported odometer mileage, most powertrain failures cluster between 25,000 and 115,000 miles, with the median around 102,000. A quarter of owners report trouble before 25,000; a quarter make it past 115,000. 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/2008/GMC/Yukon.
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.