The 2nd generation Silverado’s and GMC Sierra’s were produced from 2007 to 2013 under the GMT900 chassis code. These trucks all used engines from GM’s small-block V8 Vortec engine family, such as the 4.8L, 5.3L, and 6.2L.
While all of these engines are known for their reliability, there are a number of common problems with each. Additionally, the GMT900 platform has a number of it’s own unique problems as well – some of which I’ve experienced in our 2009 Tahoe 5.3L such as battery issues and 4WD problems.
This guide is going to cover common problems and general reliability of the GMT900 Silverado and Sierra 1500 trucks and the Vortec engines they used.
2007-2013 Silverado & Sierra Common Problems
These are the most common GMT900 Silverado and Sierra problems:
- Fuel level sensor failure
- Dead battery and frequent battery failure
- Excess oil consumption
- Faulty 4WD sensor and switch
- HVAC actuator failure
- Instrument panel failure
- Throttle position sensor failure
- Bad/failing speaker system
The common problems list might look daunting, but fortunately, the majority of these problems are relatively small and are related to sensors or small parts failing. Fortunately, none of the aforementioned problems are significant engine problems, and none of them will keep your car off the road for too long.
The 2007-2013 years are considered the most reliable Silverado and Sierra models ever manufactured. Overall, these trucks and engines are very reliable despite the long list of problems we’re going to discuss.
1. Fuel Level Sensor Failure
The fuel level sensor is known to go out frequently at the approx. 100,000 mile mark. The fuel level sensor is part of the fuel pump and reads how much gas is in the gas tank, and relays that information to the fuel gauge on your instrument cluster.
A failed sensor will result in the gas gauge giving you inaccurate readings. While this is not a major problem and doesn’t hurt driveability or performance, it could leave you stranded on the side of the road out of gas if the reading is telling you you have more gas than you actually do! In most instances however, the gauge will show that you have less gas in the tank than you actually do.
- Sporadic gas gauge readings
- Gas gauge showing empty after refilling your tank, or showing full when you know it is not
- Gas gauge shows you losing gas faster than normal
Replacement Options & Cost
Fortunately, the fuel level sensor itself is only about $25. The sensor is part of the full fuel pump unit, so you will need to access the fuel pump to DIY the repair.
Occasionally, on vehicles with a lot higher mileage, this sensor could go bad in conjunction with the whole fuel pump/sending unit. Replacing the full fuel pump is not a bad idea if your vehicle has 150,000+ miles on it, but this will run you approx. $1,500 to have a repair shop do it for you.
2. Frequent Battery Failure & Dead Batteries
On average, the battery on Silverado’s and Sierra’s goes bad every 30,000 miles. Compared to other vehicles, this is very quickly and frequently. If you are looking at purchasing one of these vehicles, budget for a new $200-250 battery every 30,000 miles. Also, make sure you always keep jumper cables in your car or a portable charger if you frequently find yourself driving in the middle of nowhere.
It’s not really known what is the cause of the frequent battery failure, but a bad anti-lock braking system pump could be the culprit. If you are burning through batteries at excessive levels, check your ABS unit and have it replaced.
3. Excess Oil Consumption
Although coming in at #3 on our list, this is probably the most common and likely problem you’ll experience with your GMT900 truck.
The excess consumption is usually caused by the active fuel management (AFM) system, which is designed to increase gas mileage. The AFM system turns off certain engine cylinders when the driver doesn’t need full engine power. This system basically turns your V8 engine into a V4.
While this technology helps improve gas mileage, it is the main cause of excessive oil consumption, and becomes a common problem at or around the 50,000 mile mark. The degree of oil consumption will vary from vehicle to vehicle, but you will likely need to add an extra quart of oil to the engine every 1,000-3,000 miles.
We recommend always keeping a quart or two of oil in your car in case the oil light comes on when you’re on a long road trip. An additional option is to disable or delete the AFM system.
4. Faulty 4WD Sensor and Switch
The 4WD transfer case is part of the drivetrain and is responsible for delivering power from the transmission to both the front and rear axles. The transfer case has a motor position sensor and a selector switch, which allows you to be able to switch between 2WD and 4WD. Over time, the sensor and switch can fail and become defective simply from wear and tear, dirt and particles, corrosion, etc. This is a common issues to run into on trucks with >100,000 miles on them, or trucks that are frequently driven through dirt, mud, gravel, etc.
If you have a failing sensor, you will receive a “Service 4WD” message and light on the dashboard. Fortunately, repairs here are cheap and easy to DIY. Check out this post for some helpful steps.
5. HVAC Actuator Failure
To simplify its function, the HVAC actuator is responsible for controlling the hot and cold air temperatures for the driver and shotgun air conditioning. The cars climate control computer will send commands to the actuator, causing it to move and create either the hot or cold air. If you have a failing actuator, the actuator won’t properly move when it receives the signal, which can cause a myriad of AC issues as mentioned in the below symptoms. If your AC is experiencing any of these symptoms, its the actuator causing the problems.
- Inconsistent air speeds
- Hot air blowing when set to cold, and vice versa
- Ticking noise from the dashboard when the car is on and air is running
- AC only blows either hot or cold, regardless of temperature setting
Like most issues on these trucks, this is more common once you exceed the 100,000 mile marker.
Replacement Guide: https://www.2carpros.com/articles/replace-blend-door-motor
Replacement Part: Chevy/GMC 1500 & 2500 HVAC Actuator
6. Instrument Panel/Cluster Failure
Again, on trucks with more than 100,000 miles, a complete or partial instrument cluster failure is common. If you are experiencing any weird gauge movements, or these symptoms below, you likely have a completely failed cluster or one that is in the process of completely failing.
- Speedometer is stuck at a certain speed or just doesn’t move
- Odometer is stuck and mileage isn’t increasing
- Fuel gauge is wrong (if this is the only thing wrong, its probably your fuel level sensor)
- All gauges stop working
- Instrument cluster works when the car is worm but doesn’t work when its cold
Warranty: has been extended on these to 7 years or 70,000 miles due to the frequent occurence. Unfortunately, warranty is going to be running up on even the newest GMT900’s soon, so you will need to have it replaced by a shop or by yourself.
Replacement Options: buy a brand new cluster, or use a repair service for your cluster.
7. Throttle Position Sensor Failure
You’re probably starting to catch on to the common theme with these cars: sensor failures. The throttle position sensor is used to monitor air intake and is mounted onto the throttle body. It monitors how open or closed the throttle body is (which in turn effects the amount of air entering the engine), which is controlled by how much the driver is pressing the accelerator pedal.
Symptoms of Failure
- Check engine warning light
- Rough idling
- Surging or jumping RPM’s
- Hesitation, stalling, etc. when trying to drive
- Reduced power message on the dash
- OBD Fault Code: P2135
Replacement Part: Throttle Position Sensor
8. Speaker System Failure
Speaker failure is common with any car as it ages, but it is especially common for GMT900 Silverado’s and Sierra’s. Typically, the speakers in the door are the first to go out, followed by the remaining speakers if you experience full speaker system failure. Although, a lot of the time you will just lose your door speakers and the rest of them will continue to work just fine. Occasionally, the speakers will stop working, start working, then stop working again.