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NHTSA — Engine Problems


hardly worth mentioning
Crashes / Fires:
0 / 0
Injuries / Deaths:
0 / 0
Average Mileage:
65,353 miles

About These NHTSA Complaints:

This data is from the NHTSA — the US gov't agency tasked with vehicle safety. Complaints are spread across multiple & redundant categories, & are not organized by problem.

So how do you find out what problems are occurring? For this NHTSA complaint data, the only way is to read through the comments below. Any duplicates or errors? It's not us.

2008 Hummer H3 engine problems

engine problem

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2008 Hummer H3 Owner Comments

problem #9

Jun 032016


  • 107,000 miles


The security lock system on my Hummer H3 intermittently flashes during start causing the vehicle to not crank. Normally I have to wait 10 to 20 minutes for the system to reset itself and she starts right up, but today it's been 8 hours. Finally I had to call for a tow to the GM dealership. We got lucky today. At 10am my wife thought she was going into labor, we get to the truck and no start. Just a flashing security lock symbol flashing at me. Ended up using her car. This is definitely a safety concern, what if her water had broke or my son was needing medical attention. I know GM knows of this defect because I have read thousands of complaints about this exact problem online. They will not fix it unless made to.

- Orlando, FL, USA

problem #8

Feb 122014


  • 77,079 miles
Upper rail rubbed against the plastic tank on the radiator, creating a crease that fractured, spraying radiator fluid all over the engine compartment. Radiator had to be replaced. Tech advised that the design of the vehicle was faulty because the rail was installed too close to the radiator. He shimmed it to prevent it from happening it again.

- Altoona, PA, USA

problem #7

Jun 212015


  • 74,000 miles
The contact owns a 2008 Hummer H3. While driving 45 mph, the temperature gauge displayed that the vehicle's temperature was very high. The contact merged to the side of the road and poured antifreeze into the vehicle. The failure recurred numerous times. The vehicle was taken to a dealer. The technician diagnosed that the radiator had fractured and needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was 74,000. The VIN was unavailable....updated 08/10/15

- Matawan, NJ, USA

problem #6

Apr 242015


  • 68,000 miles


While driving I noticed heavy smell of antifreeze.. I took to local shop and we noticed antifreeze all over engine. Radiator had crack on top. After research I see multiple complaints online with other Hummer owners same issue. Had to replace radiator. Mechanic said ther radiator rubs and bounces against the frame causing crack.

- Plainview, NY, USA

problem #5

Nov 072014

H3 5-cyl

  • 82,000 miles
Without any warning, the engine began to misfire and stall out after starting from a green light. It only lasted about 10 seconds. After this, the engine quit misfiring and began to have an audible whine come from under the gear shifter. This was subsequently diagnosed by electronic means as an intermittent misfire and accelerator pedal position sensor. After examination by a mechanic, in the lower portion of the engine a bolt holding in place one of the balancers worked itself free. The entire bolt was displaced from its original location and the threads were protruding out of the plate behind the flywheel in the area of the rear main seal causing a significant loss in oil. Upon further inspection after the engine was removed, multiple components appeared damaged as a result of the bolt getting stuck in one of the internal chains. The whining noise was a result of the chain rubbing against the remains of the bolt that was lodged and partially expelled from the lower rear of the motor. Finally, to be clear, this incident appears to be the result of a bolt being improperly torqued, machined or the balancer being improperly machined and matched for the bolt. Again, the entire bolt (including threads) was free from the component it was installed in.

- Troy, OH, USA

problem #4

Apr 052013

H3 5-cyl

  • 62,200 miles
Radiator end tank ruptured releasing coolant on everything under the hood and getting on the windshield. Research of this finds that there is a defect in the design of the factory radiator which GM refuses to take action on. Had this happened at higher speeds, this could have been a much worse situation.

- Louisville, KY, USA

problem #3

Jun 152011

H3 5-cyl

  • miles


The radiator had a crack in it when we bought the HH3, in 6-2011 which was replaced with a new factory radiator. It is now March 0F 2013 and we have another crack in the radiator. We contacted" savvy" Goodyear in long beach, New York who replaced the first one and they said it is not covered. Really does a radiator only last 2 years. They indicated that GMC would not cover the replacement. I see that this has happened to several vehicles shouldn't there be a recall?

- Winchester, VA, USA

problem #2

Mar 152013

H3 5-cyl

  • 52,547 miles
I bought a 2008 Hummer H3 four months ago at 49,956 miles, when last week I noticed I had a bad coolant leak causing the fluids to remain on the top of the engine, the fan shroud, etc. Had it towed back to the dealership where I bought it from because its a 48 miles drive and didn't want to take the chance of anything overheating. Took it in on Friday morning got it back Monday afternoon when I was told the radiator was cracked. After looking on the internet seems like everyone seems to be having this problem. The mileage when the dealership received it on Friday was 52,547.

- Piqua, OH, USA

problem #1

Oct 102012

H3 5-cyl

  • 65,355 miles
Radiator has cracked due to manufactures defect.

- Sullivan, MO, USA

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