Hummer H3 Reliability and Common Problems

Lisa Conant, Automotive Features Reviewer at CarParts.com

Reviewed by

Lisa Conant, Automotive Content Specialist

Automotive Features Reviewer at CarParts.com

Written by CarParts.com Research Team - Updated on April 23rd, 2024

Reading Time: 5 minutes
Summary
  • The Hummer H3 enjoys fair reliability ratings. The latest model (2010) scored a reliability score of 3 out of 5.
  • The 2006 model has the highest reliability ratings. It also nabbed a 5-star rating for both driver and rear passenger side crash simulations conducted by the National Highway Traffic Administration (NHTSA).
  • Some of the model’s common issues include cracked radiators, air conditioning/heater problems, and fuel level sensor issues.

If you’re looking for an off-roader with stable handling and comfortable seats, you can never go wrong with a Hummer H3. After all, it was always one of the top contenders in its segment while it was still in production. But just like any vehicle out there, it may develop issues over time. If you drive an H3 or have plans to buy one, it will help to read up on its reliability ratings and the common problems you may encounter with it as it racks up mileage.

Are Hummer H3s Reliable?

The Hummer H3 has a fair reputation in terms of reliability. J.D. Power gave its latest model, the 2010 Hummer H3,  a reliability score of 3 out of 5. Older models also have good reliability ratings. According to the consumer review page Edmunds, most owners gave the 2006 Hummer H3 a high rating in terms of reliability.

Aside from having good reliability scores, this SUV also scored well in safety ratings. The 2006 Hummer H3 got a 5-star rating for both the driver and rear passenger side crash simulations conducted by the National Highway Traffic Administration (NHTSA).

Hummer H3 Common Problems

As reliable as it is, the Hummer H3 isn’t perfect. Just like other SUVs, it can develop problems due to faulty or worn-out parts as it gets older. Here are some of the most common Hummer H3 issues across its model years:

Cracked Radiator

Many 2008 Hummer H3 owners have complained about coolant leaks caused by a cracked radiator. According to reports, this is a common problem for the model year. Fortunately, replacing the faulty radiator solved the issue on most affected vehicles. A replacement radiator can cost anywhere between $100 and $750 plus labor costs.

A/C or Heater Problems

A/C and heater issues are another common complaint about the 2008 Hummer H3. Many owners have reported that their HVAC (heating, ventilation, and air conditioning) harness burned out at around 90,950 miles. Some drivers said that it was a recurring problem, as they had to replace the harness multiple times because it wears out quickly.

A/C and heater issues are a relatively common complaint about the 2008 Hummer H3. Image source: Wikimedia.

Several owners also complained that their H3’s blower motor failed after about 123,000 miles. They had to replace their blower motor to get their SUV back in top shape. If you’re experiencing issues with your vehicle’s HVAC system, don’t hesitate to take it to your mechanic for proper diagnosis and repair.

Fuel Level Sensor Issues

Some 2006-2008 Hummer H3s are prone to fuel level sensor problems. According to reports, the fuel level sensors of the affected vehicles may fail, causing erratic fuel gauge operation. Technicians recommend replacing the whole fuel pump assembly module on high mileage H3s to resolve the issue.

Transmission Problems

Transmission problems have been common in many 2007 Hummer H3s. Most issues happen at around 132,000 miles.

Transmission problems have been reported by some owners of the 2007 Hummer H3. Image source: Wikimedia.

Several owners have complained that their Hummer lost power and exhibited shifting problems while they were on the road.  Others reported that their transmission was shaky for a few days. Most of them also had trouble shifting into gears.

Rebuilding the transmission usually solves this issue. Repairs for this type of problem can cost up to $1,650.

Leaking Valves

2006 was the worst year for the H3 because most of the problems reported for this model year are related to the SUV’s engine. Many owners have complained that the valves in their H3’s cylinder head started leaking at about 87, 750 miles. Some reported that their engine started to misfire multiple times.

Several 2006 Hummer H3 drivers found out that their SUV was burning oil when they brought it to a repair shop. Some of them also had issues with oil leaks. Replacing the cylinder head valves or the cylinder head solved the issue on most affected vehicles.

Rough Engine

Several owners of 2006 Hummer H3s have also complained about a rough-running engine. Some of their mechanics replaced the spark plugs and ignition coils to solve the issue, but the engine still runs rough after the repair.

Many drivers also had to deal with issues like multiple misfires, low compression, and white smoke coming from the tailpipe. According to reports, replacing the head gaskets and leaking valves solved the issue on some affected vehicles. Repairs for this type of issue can reach up to $3,100, making it one of the worst problems for the Hummer H3.

Cylinder Head Failure

Another common complaint about the 2006 model involves the faulty cylinder heads in some of its units. The issue is usually associated with an illuminated check engine light. Good thing this issue can easily be solved by replacing the faulty cylinder head. Repairs for this issue can also reach as high as $3,450.

These are only some of the issues you may encounter with your Hummer H3 as it gets older. If you’d like to find out if your Hummer H3 is part of any recall, you can check out this article. You can also check out the NHTSA website for more information.  As long as you know the potential problems you may encounter with your H3, driving it comes with minimal risk.

Get a New Radiator Delivered to Your Home

The Hummer H3 isn’t the only vehicle that often has radiator-related woes. Since driving with a bad radiator can lead to more engine issues, you must prioritize replacing it as soon as possible. Get your vehicle back on the road with a replacement radiator from CarParts.com.

CarParts.com offers competitively priced, high-quality vehicle accessories and replacement parts, including radiators for various makes and models. Find the most suitable part for your car or truck by plugging the appropriate details in our website’s vehicle selector. Ordering a radiator takes only several taps on your phone’s screen, and our on-hand products ship from the nearest distribution center. As long as you live in the continental US and order before noon ET, you can expect to get your new radiator in as fast as two business days. If you need assistance, our customer service team is available 24/7.

Don’t wait for your car’s radiator to fail. Browse CarParts.com’s wide selection of radiators and order one today.

About The Authors
Reviewed By Lisa Conant

Automotive Features Reviewer at CarParts.com

Lisa Conant grew up in Canada around a solid contingency of gear heads and DIY motor enthusiasts. She is an eclectic writer with a varied repertoire in the automotive industry, including research pieces with a focus on daily drivers and recreational vehicles. Lisa has written for Car Bibles and The Drive.

Written By CarParts.com Research Team

Automotive and Tech Writers

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Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.

View Comments

    • Just want people to know that my hummer h3 has had some issues. Running rough not starting and so on. Just about all my issues are due to the fuse box under the hood. Everything was corroded. The most recent was one of the nuts holing the main wires coming into the fuse box. The nut actually fell apart when I took it off. The fuse box issues mimic a whole slew of issues. Like bad plugs, Mass air flow problems and rough or not starting at all. It's a good place to look.

      • Thank you for your advice e I have a 06 Hummer I really enjoy it although it's not as good of a wheeler as a Jeep Rubicon .I will not waste time according to your experience with the Hummer and clean my fuse box and buy a new head to eliminate down time .I am a prospector I spend most my time off road it does a good job I am however having issues with my traction controll I have 156.270 on it and it's doing fine .

  • I HAVE A 2006 HUMMER H3 ONLY ISSUE LISTED ABOVE WE HAVE HAD IS THE RADIATOR. SHE HAS CLOSE TO 200 THOUSAND ON HER .

  • I own a 2008H3 hummer with a 3.7 L five cylinder in it replace the radiator and I’ve rebuilt transmission it has 185,000 miles on it I would not trade it for the world. Well, I would consider trading it for the new electric hummer. Lol but only the electric hummer.