The Hummer H2 was equipped with the 4L65E in most models and the 6L80 in 2008 models. But they aren’t without their problems though, so let’s look at some of the most common Hummer H2 transmission problems, look at cost estimates and figure out what you can do about them.
Hummer H2 Transmission Models
Hummer H2: 4L65E Transmission
Hummer H2: 6L80 Transmission (2008)
Hummer H2 Transmission Replacement Cost Estimate
Pricing varies by model. To be 100% sure on pricing, have your VIN# handy and use our Get An Estimate feature to look up your transmission by VIN#.
Replacement Hummer H2 Transmission Prices:
|Transmission||Street Smart Transmission||Autozone||Advance Auto Parts|
|4L60E / 4L65E||1480||1507||1599|
|6L80 / 6L90||2320||2450||2480|
What are the DTC codes related to Hummer H2 transmission problems?
P0766 – Failed Shift Solenoid D – This DTC can be stored when there is a problem with a shift solenoid or the valve body.
P2703 – Failed Friction Element D – This trouble code can be triggered by a failed friction element like a clutch disc.
P0720 – Failed Input Speed Sensor or Output Speed Sensor – This trouble code is caused by a bad speed sensor on the transmission.
P0730 – Incorrect Gear Ratio – This issue could be caused by a number of problems, including a fault in the transmission control module, dirty transmission fluid, or a bad transmission solenoid.
P0657 – Voltage Problem in the ‘A’ Circuit – This transmission problem is often caused by a short, or bad ground on the PCM or PCM wiring harness.
P0700 – Malfunction in the transmission control system – This DTC is often triggered when there is a problem with the TCM, a wiring harness, a solenoid, or the valve body.
P0715 – Input/Turbine Speed Sensor Malfunction – This code typically gets stored when the input sensor cannot read the engine RPM, which can prevent the transmission from appropriately shifting gears.
P0717 – Input/Turbine Speed Sensor No Signal – This trouble code is generated when the PCM does not get a signal from the input speed sensor, which will prevent the computer from being able to determine when the transmission needs to shift.
P0791 – Intermediate Shaft Speed Sensor ‘A’ Circuit – This error can occur when there is a problem with the intermediate shaft speed sensor, most likely due to a bad sensor, wiring problem, or a failed shift solenoid.
P0793 – Intermediate Shaft Speed Sensor Circuit No Signal – The computer will generate this DTC when it cannot communicate with the intermediate shaft speed sensor.
Hummer H2 Transmission Recalls
Hummer H2 Technical Service Bulletins (TSB)
Common Problems with the Hummer H2 Transmission
Lack of Response
Grinding or Shaking
Whining, Clunking or Humming
Refuses to Go Into Gear
Torque Converter Issues
Valve Body Issues
Transmission Noisy in Neutral
No 3rd or 4th Gear
No 1st or 2nd Gear
Trouble Codes / Check Engine Light
Can I drive with a transmission problem?
If your Hummer H2 can still make it up and down the road, you might say “It’s fine, I’ll just drive it until I can get it fixed”. But that is not always a good idea, depending on the symptoms. You see, there are a lot of (very expensive) moving parts inside of a transmission, and if something isn’t right, continuing to drive with a transmission problem could damage something else.
How often does a Hummer H2 transmission need to be replaced?
The overall lifespan of a Hummer H2 transmission largely depends on how well it was maintained. Factory design flaws also factor into this equation, along with how/how hard you drive. But on average, we’ve seen the Hummer H2 transmission last for between 130,000-180,000 miles. A high quality replacement transmission however, can last considerably longer if all of the factory design flaws have been addressed and the vehicle has been maintained.
How are Hummer H2 transmission issues diagnosed?
It is fairly easy to guesstimate what the root cause of your Hummer H2 transmission problems might be, but you won’t truly know unless you have the right tools and experience. A good mechanic or transmission repair center will be able to connect your truck to a computer and find out which diagnostic trouble codes (DTC’s) have been stored. Once they know what to look for, they can perform a visual inspection to verify the problem.
How is a Hummer H2 transmission replaced?
In order to replace your Hummer H2 transmission, the truck has to be lifted from the ground in order to gain access to all of the parts that will need to be unbolted. Then the transmission can be lowered to the ground (typically with a transmission jack), so the new transmission can be installed. Once it is in place, for the 6L80, the vehicle PCM will have to be reprogrammed / reflashed to accept the new transmission using the latest GM subscription.
Recommendations for Hummer H2 transmission issues?
To save time and get back on the road faster, have your 17-digit truck VIN# handy and you can get an online quote for a reman Hummer H2 transmission here, then find a local shop using our Find a Shop guide to install it for you.
How to Solve Hummer H2 Transmission Problems
Solution A: Buy a Used Hummer H2 Transmission
The quickest way to fix your transmission problems is to simply buy a used transmission or used transmission. These can be found at most junk yards, and they often come with a 30-90 day warranty. However, there’s no way to determine the actual condition of the internal components, so you could be spending a bunch of money to have the exact same problems. Plus, that warranty only covers the transmission if it’s defective, not the labor costs that you’ll have to pay.
Solution B: Buy a Rebuilt Hummer H2 Transmission
Another option would be a rebuilt transmission or rebuilt transmission. A local repair shop will remove your transmission, then install a bunch of new parts during the rebuild. The problem here is, the skills and experience of each transmission rebuilder will vary widely from shop to shop, so you could have problems from something that wasn’t adjusted properly. And the 1-2 year warranty might only cover you at certain transmission repair shops, in a specific geographical area.
Solution C: Buy a Remanufactured Hummer H2 Transmission
Many owners depend on their vehicle to commute and get things done. Their gasoline engines are designed to go 100’s of thousands of miles, so it makes sense to invest in a remanufactured transmission.
What Problem Does Your Hummer H2 Have?
Let us know the year, mileage and problem you’re having as well as any trouble (OBD) codes you’ve found. If you’ve been given a quote or paid for a repair, we’d like to hear about that too!