This service bulletin explains how to measure for oil consumption and possible reasons for loss of oil.
full bulletin at NHTSA ↗2006 Hummer H2 engine problems
moderate 5 complaints filed with NHTSA · avg repair $3,100 · see engine across all vehicles →
Complaints
5
Recalls
0
Avg fix
$3,100
When does it fail?
Of the 5 engine complaints filed for the 2006 Hummer H2, here's the actual mileage breakdown — failures cluster heaviest at 50,000-75,000 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
Engine accounts for 20% of all owner complaints filed against this vehicle, across 4 categories tracked.
No new NHTSA engine complaint has been filed on this vehicle in over 17 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 engine 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.
This service bulletin explains how to measure for oil consumption and possible reasons for loss of oil.
full bulletin at NHTSA ↗This service bulletin provides guidelines and diagnostic/repair information to technicians regarding vehicle engine oil consumption.
full bulletin at NHTSA ↗This technical bulletin advises of a new fuel injection cleaner kit used for decarbonizing the intake valves to correct conditions of rough idle, Crank no start, extended crank or misfire, MIL with DTCs, and explains how Top Tier fuels should be used to reduce carbon build-up.
full bulletin at NHTSA ↗This service bulletin provides service information to technicians on guidelines to replace Oil Cooler, Oil Cooler Lines and Oil Tank if the engine was replaced where large amounts of debris has flowed throughout the oiling system.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
What owners are reporting 5 most recent
The air filter covers on my h2 get hot and start deforming "ripples" in the plastic. The plastic molding between them where the wipers go through deforming also. I have replaced 4 air filter covers in under 6,000 miles. And 1 wiper molding. I am not sure of the consequences. Hummer says it's no problem. I have 1 of the air filter covers that has failed in my possession. According to gm/Hummer…
Check engine light came on and wouldn't go out. Took it to the garage and they pulled up the code po442, EVAP leak. They did a smoke test and found out the fuel pump unit was all rusted out and also the straps holding the fuel tank in was all rusted out. One of the straps was completely broken off and only one was holding the tank but it was all rusted. Called a dealer because this part should…
1. Normal driving in town and highway 2. Failure of the drivers side exhaust manifold bolts; causes exhaust gases to fill engine compartment and bypasses the catalytic emissions equipment. *tr 3. Drivers side head had to be removed, broken manifold bolts extracted from the head, new manifold and stronger manifold bolts installed. *tr
2006 Hummer h2 sut 6.0 liter engine exhaust manifold bolts broken off. *kb
1. Normal driving in town and highway 2. Failure of the drivers side & passenger side exhaust manifold bolts; causes exhaust gases to fill engine compartment and bypasses the catalytic emissions equipment. 3. Drivers side head had to be removed, broken manifold bolts extracted from the head, new manifold and stronger manifold bolts installed. *tr
Had engine trouble with your 2006 Hummer H2?
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 engine problem on the 2006 Hummer H2?
It's a documented issue but not catastrophic. 5 complaints have been filed. Repairs average $3,100 and most owners catch it before it causes a breakdown.
At what mileage does the engine typically fail?
Based on the 5 complaints filed, engine issues most often appear around 53,003 miles. Some report problems earlier; some make it well past 150,000 with no symptoms. Maintenance habits matter — vehicles that received timely fluid services and were not regularly overworked tend to last longer.
What does it cost to fix?
Independent shops typically charge around $3,100 for engine 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 engine?
No active recalls currently cover engine 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/2006/Hummer/H2.
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.