Hummer H3 Engine Problems

Owners have filed 176 complaints about engine & cooling problems with the Hummer H3 — 22% of all H3 complaints. The worst model years are 2006 (87), 2007 (56) and 2008 (22). Problems typically start around 72,000 miles. No engine recall has been issued for the H3.

176complaints
2006worst year
72ktypical miles
0related recalls
1crashes
4fires

Engine complaints by model year

20062007200820092010875622101
Engine complaints per model year, Hummer H3.
YearComplaintsShare of year's complaintsTypical mileage
2010114%60,000 miles
20091014%74,000 miles
20082219%74,000 miles
20075624%74,000 miles
20068724%70,000 miles

Which parts fail

  • Engine
    7
  • Cooling system › Radiator assembly
    2
  • Cooling system
    2
  • Engine › Oil/lubrication › Pressure/temperature sensor
    1
  • Exhaust system › Manifold/header/muffler/tail pipe
    1

Components named in complaints (engine, cooling system, oil leaks, timing chain, exhaust).

Mileage when the problem started

  • Under 25k
    1611%
  • 25k–50k
    149%
  • 50k–75k
    5335%
  • 75k–100k
    2617%
  • 100k–150k
    3624%
  • 150k+
    64%

What owners report

The contact owns a 2009 Hummer H3. The contact stated that while attempting to start the vehicle, the vehicle failed to start. The contact waited for a while before the vehicle started. The contact stated that the vehicle was slow to start. The contact stated that while her husband was at the store, he waited for 15 minutes before the vehicle started. There were no warning lights illuminated. The vehicle was taken to an independent mechanic who replaced the battery and starter, but the failure recurred. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was not contacted. The failure mileage was unknown.

2009 H3 · Jan 2021

P2135 throttle/pedal position sensor/switch a/b voltage correlation that puts the vehicle into ?stabilitrak disabled", "traction control disabled", and "reduced engine power". While there is a TSB#11-06-04-007b regarding this issue and warranty coverage; unfortunately it does not apply to my engine. However, since this is a widely know issue, and this vehicle is experiencing the same conditions, one would think that my vehicle would be serviced under this TSB extended warranty coverage. 12/04/2014: first service attempt: clear code everything tests fine, let?s see if it happens again. 12/10/2014: second service attempt: both throttle body and acc pedal position sensor tested "good". Weak battery - replace battery. 12/22/2014: third service attempt: tech replaced accelerator pedal. Relearned throttle/idle. 12/26/2014: forth service attempt: relearned throttle/idle procedure. …

2009 H3 · 74,000 miles · Nov 2014

The contact owns a 2008 Hummer H3. The contact stated that the vehicle intermittently failed to start up without warning. The contact stated that after waiting ten minutes the vehicle started. The contact stated that recently the failure had become more frequent. The contact had taken the vehicle to a dealer however, the mechanic was unable to determine the cause of the failure. The manufacturer was not notified of the failure. The vehicle was not repaired. The failure mileage was approximately 1,000.

2008 H3 · 1,000 miles · Oct 2008

Engine was replaced at 163,000 miles now at 168,000 miles the frame is rusted beyond repair and is about to give at any moment nothing really left near rear axels. This could have definitely caused a horrible accident to myself or others having a big car just give way and collapse. Took it to mechanic who warned me first then next day took it to body shop that said nothing could be done. Basically both said get rid of it for parts as fast as you can and don't look back. After the body shop guy actually showed me the rusted out areas i was scared to even drive it like the 10miles back to my house. It sucks after spending all that money on an engine and now having this issue and now having to buy a new car.

2008 H3 · Dec 2023

The contact owns a 2007 Hummer H3. The contact stated while driving at 50 mph, the vehicle started to overheat and stalled. The contact stated the temperature and the check engine warning light were illuminated. The vehicle was then towed to a local dealer where it has yet to be diagnosed due to the battery needing to be replaced. The vehicle was not repaired. The contact had the vehicle serviced under NHTSA campaign number: 15V421000 (Visibility) prior to experiencing the failure. The manufacturer had not been informed of the failure. The failure mileage was approximately 160,000.

2007 H3 · 160,000 miles · Jun 2021

Everything from: electrical, air condition, stabilitrack system, which cost me over $600.00 still not working properly. Leakingsun roof censors, I was made to pay for that still dont work. I paid over $8,000.00, or more. When ever I brought my vechicle in, I was forced to for something else, my vechile only had about 22,000.00 miles. I was taking it to GMC/vera Cadillac 300 pembroke pines, fl 33025, ph:[phone], service manager mr.gustavo, edwin montoya. I have over 50 pages documents about fake repairs, my vechicle is wrost off now than before. It also has safty issues, mold/medw, ac overheating, airbag not working, etc. I am afraid for my safty.

2007 H3 · 22,000 miles · Dec 2013 · crash

The contact owns a 2006 Hummer H3. The contact stated that the frame was rusted on the driver's side. The check engine warning light was illuminated. The contact looked underneath the vehicle and was able to see through the subframe. The contact also noticed cracks in sub frame. The contact was concerned about driving the vehicle. The vehicle was taken to an independent mechanic who determined there was an issue with the temperature sensor. While receiving an oil change, it was determined that the subframe was rusted. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was contacted and confirmed that there was no recall coverage for the failure. The failure mileage was approximately 130,000.

2006 H3 · Engine › Oil/lubrication › Pressure/temperature sensor · 130,000 miles · Oct 2025

On the electrical, I refer to my air conditioning and heater. When I have my air selection to coldest and I drop 1 click for it to be less cool, my heater turns on and at times it smells like something burning. I have to turn it off . On the engine, after I hit 90,000 miles, I have to fill up my engine oil every 2-3 weeks because my vehicle is burning it quick or something. It doesn't leak oil at all. The oil just seems like it's burning somewhere and I ha e to be waisting money to buy oil $30 to $60 a month. Please help. Thank you!

2006 H3 · Jan 2025

Frequently asked questions

Which Hummer H3 years have engine problems?

By NHTSA complaints, the 2006 (87), 2007 (56), 2008 (22) and 2009 (10) model years. Engine complaints make up 24% of all complaints for the 2006.

Is there a recall for Hummer H3 engine problems?

No. NHTSA lists no engine & cooling recall for any Hummer H3 model year. A widespread problem may still be covered by an extended warranty or a manufacturer service bulletin, so ask a dealer.

At what mileage do Hummer H3 engine problems start?

Across all years, half of the complaints with a recorded mileage happened before about 72,000 miles; 20% happened before 50,000 miles.

What part fails most often?

Owners most often name the engine (7 mentions), followed by the cooling system › radiator assembly (2).

Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.