Hummer H3 Hummer H3

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Hummer H3 Engine Problems and Repair Histories

Hummer H3 repairs by problem area

Engine (31%)

Transmission and Drivetrain (14%)

Brakes and Traction Control (11%)

Suspension and Steering (9%)

Electrical and Air Conditioning (22%)

Paint, Rust, Leaks, Rattles, and Trim (10%)

Other (4%)

Chart based on 245 repairs.

Hummer H3 engine repair cost distribution

$2500+ (23%)

$1000 - $2499 (11%)

$500 - $999 (17%)

$100 - $499 (40%)

< $100 (9%)

Chart based on 35 repair trips. The repair cost chart excludes repairs made under warranty, do-it-yourself repairs, and repair trips that include maintenance.

2008 Hummer H3

Engine not specified

62620 mi

C $460
Check engine light stays on. 

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2008 Hummer H3 4dr SUV

295-horsepower 5.3L V8 4-speed automatic AWD w/low range

143000 mi

US $7500
#5 bearing spun. Full engine replacement. 
47000 mi Total engine failure, 5.3L V8 
95000 mi

US $108
Oil Pan Gasket needed replacing, oil leak Replaced cat back exhaust 
110000 mi

US $15
small coolant leak 
120000 mi

US $25
Simple preventative maintenance- Oil Change, air filter cleaning (k&N) and MAF and throttle body cleaning (rough idle) 
75000 mi

US $1750
Top of radiator leaking because of no padding on upper retaining bracket. Original OEM design and install. DTC P0121. tech found the throttle body bad. 

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2008 Hummer H3 4dr SUV

242-horsepower 3.7L I5 4-speed automatic AWD w/low range

45000 mi

US $170
Engine service light replace Gas Cap.1st. according to repair manual. Then had to replace Gas tank Pressure valve at gas tank. 
54000 mi

US $748
Radiator cracked at top causing leak. Vehicle also has a rough idle. Cause of Idle unknown 
82000 mi Occasional engine loss of power under high steering load when just starting up after about a week of sitting. 

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2007 Hummer H3 4dr SUV

242-horsepower 3.7L I5 5-speed manual AWD w/low range

118000 mi

US $55
Water Pump leaking (bearing) 
67000 mi

US $2600
Cylinder number 5 misfiring, valves stuck. Entire block needed rebuilt. This is a common problem with this engine and GM is ignoring. 
82000 mi

US $300
Servo valve in sensor showed engine light, design change made a $100 part cost $200 with $100 installation. 
95000 mi

US $807
Radiator needed to be replaced as well as a u joint. 

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2007 Hummer H3 4dr SUV

242-horsepower 3.7L I5 4-speed automatic AWD w/low range

58000 mi Master cylinder failure - have to REPLACE Engine 
82000 mi

US $600
Overheating replaced radiator. 
39700 mi Check engine light on. Small evap leak found. Smoke test. Dealer replaced vent solenoid and gas cap. Retested, no leaks found. 
36700 mi hard idle, replaced stock air intake with k/n air intake, also added g force power chip. idle now better, gas mileage up 6 to 7 m.p.g. 
62000 mi

US $2850
Complete cylinder head replacement. Top engine tear-down and reassembly. Due to engine misfire fault code and rough idle concerns. Poor acceleration after long haults at stop signals. 
85000 mi

US $250
At 90000 miles Radiator's plastic top tank seams started leaking coolant and loss of cooling system pressure. 
93300 mi

US $5000
Poor engine cylinder head design at manufacturer. Engine studder and misfire at idle while in gear with foot on brake.Replaced cylinder head w/ new and problem returned after appx. 4000 miles. 
70000 mi Radiator went bad, and the Hummer dealer replaced it and flushed the cooling system for free.. Wright Hummer in Wexford PA is the best dealer I have seen that takes customer service serious.. They are #1. 
69800 mi

US $3000
Cylinder Head is bad. Needs to be completly replaced. 
47500 mi Catalytic converter was replaced. 
60500 mi

US $240
Can position sencor. 
109000 mi

US $417
No power on acceleration. Sluggish. Still dealing with it. 
109500 mi

US $777
Loud rattling. Replaced motor mounts and transmission mount. 
86000 mi

US $3899
catalytic converter bracket broken. Bolts broken off in head. replaced head and catalytic converter because bracket and converter are one piece. 
112840 mi

R 180
Thermostat replacement. 
68000 mi

US $50
Engine Light On; vehicle running sluggish 
70300 mi

US $600
Catastrophic water pump failure 
77000 mi

US $100
Lower radiator hose and thermostat 
58300 mi

US $1290
Water pump replacement 
67000 mi

US $1200
Radiator split apart and had to be replaced 
99200 mi

C $300
Kept shutting down while driving, traction control failing, service stabilizers 
111440 mi

C $850
broken water pump 

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2006 Hummer H3

Engine not specified

58000 mi Coolant also leaking. 
43000 mi Started H3 and it shut down, would not start, called OnStar for diagnostic check, found ECM needed replaced as well as a new battery. Roll back picked it up and delivered to dealer. Did not cost me a dime. 
53000 mi Replace accelerator pedal sensor.  

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2006 Hummer H3 4dr SUV

220-horsepower 3.5L I5 5-speed manual AWD w/low range

98000 mi

US $7200
A Rod in the engine failed. The entire engine was replaced along with a new clutch. 

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2006 Hummer H3 4dr SUV

220-horsepower 3.5L I5 4-speed automatic AWD w/low range

10000 mi The engine light came on and had to be completly reset. The computer had blown a chip. 
7200 mi Cylinder head replaced- under warranty. 
89300 mi

US $2000
Fuel Tank leaked had to replace it. Upstream Oxygen Sensor bad, had that replaced. Fuel pump rusted, connectors broke and had to replace pump and a fuel hose. 
95000 mi

US $15
Radiator Cap Leak 
67000 mi

US $70
EVAP canister failed and needed replacement... 
82000 mi Needed Heads 
93000 mi Replaced thermostat. 
99000 mi

US $40
Error code P00014 timing error. Replaced crankshsft solenoid. 
35000 mi Engine light. Took in. Code: P300. Did leak down test. Confirmed - #3 cylinder head has a 70% leak. Per TSB - replace cylinder head. Parts ordered. Will take 3 weeks to get. 15 other H3's ahead of me for replacement on head.  
37000 mi Install Cylinder Head from February visit. 
25000 mi Engine blown- 80% leakdown in #3 cyl and significant leakdown in the remaining 4. Started with intermittant CEL's and progressed to very rough idle, power loss, and single digit fuel economy. 
10000 mi Traction control problem ...they could not suplicate in the shop...Happened again today, Feb 10th, got code from onstar this time, will make another appointment 
10000 mi Needed sensors replaced. 
14300 mi ECM replaced. 
17980 mi engine shuttered on initial start-up each morning. Dealer reflash of ECM. Shutter now gone 
35340 mi Check engine light on, due to emission evaporation, vent sensor malfunction. 
50000 mi Traction control can be turned on and off on vehicle. Traction control was not able to be turned off. PBM computer module defective. 
139700 mi

US $307
Slighty overheating, thought it was the thermostat so I had it replaced at a local shop, was not thermostat, the thermostat guage went out and had to be readjusted for $100 at dealership. 
152000 mi

US $976
Started driving about a mile down the road, went dead, would not fully start back up. Would only start up for about 2 seconds, then would do a horrible idle and go dead. Ended up towing it and replacing the fuel pump. 
80000 mi engine wouldn't start--fuel pump not pumping. I removed the circuit breaker and reinstalled---pump started pumping and no trouble since 
88000 mi engine would turn over but not start--fuel pump not operating 
74000 mi

US $250
Check engine light was on and the thermostat was replaced which fixed the problem. 
91700 mi

US $483
Radiator was leaking at the top. Replaced radiator. 
95000 mi

US $50
Hard to start in cold. Replaced spark plugs. 
74000 mi

US $1000
Power steering belt replaced; worn out 
72000 mi

US $140
check engine light on, OBD II code indicated a bad evap solenoid, also got messages about fuel cap being loose. Replaced the evap solenoid, issue fixed. 
68000 mi

US $300
crack in top of radiator assembly. replaced the upper assembly at dealer. 
66320 mi

C $350
replace spark plug coil 
95000 mi

US $395
Ignition key could not be removed from ignition. Replaced two (2) sensors, did not correct problem. Disconnected brake switch. 

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2006 Hummer H3 4-door

5-cylinder automatic 4WD

7000 mi Needs new head in cylinder one 
9000 mi Needs new head in cylinder one. Repair period started in May and finished over a week later in June. 
79000 mi

US $400
Dreaded cylinder head problem found mainly in the 06 H3. 

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2006 Hummer H3 4-door

4-cylinder automatic AWD

3000 mi Vehicle stability failure. Please service message came on and I was unable to switch from 4wd drive. These buttons did not work. Mechanic said it was the encoder motor. 

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2006 Hummer H3 2-door

Engine not specified

21000 mi Bad cylinder head. Ordered replacement. 

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Hummer H3 Engine Problems

See our lemon odds and nada odds page to see vehicles with no repairs or vehicles with more than three repairs. To see how frequently Hummer H3 problems occur, check out our car reliability stats.