Q: Why does my 2007 GMC Sierra Classic shifts from 1st gear to overdrive?
Truck will shift from 1st to overdrive, what's the cause?
My car has 158890 miles.
My car has an automatic transmission.
Hello. Most of the time this is caused by a pressure issue within the transmission. It can also occur of there is a major internal failure as that is what the computer does to try and protect the transmission. I would scan the computer for any codes first. Any codes would tell me what the computer may see as a problem. If there are not any codes then I would check the pressures out in the transmission. If you want to have this properly diagnosed then you should take the vehicle to a transmission specialist.
The statements expressed above are only for informational purposes and should be independently verified. Please see our
terms of service
for more details
Get an instant quote for your car
Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing
What others are asking
How do I tilt the steering column?
Steering your truck is supposed to be easy and comfortable. If at any point, you are uncomfortable in steering your vehicle, you can adjust the tilt on the steering column. To adjust the tilt. Pull down the lever on the...
Car shaking at 50 MPH
Shaking at higher speeds is usually related to something that is rotating. Most of the time this will be the wheel and tire assembly. If you have tires that are worn unevenly, or if any of them have a manufacturer...
Car overheating after new water pump
Hello. It sounds like you may have a couple of issues going on with your vehicle. The overheating is the first concern. If it is randomly overheating then a block test needs to be done. This would indicate a leak...
Car groaning when turning
Sometimes air can get sucked into the power steering lines and the bubbles going through the power steering pump. This causes the growling you are describing. I would suggest having a qualified mechanic diagnose the noise (https://www.yourmechanic.com/services/car-is-making-a-noise-inspection) to ensure that...
Can I install a turbo on my truck?
The short answer is yes. You can install a turbo on your truck. You could install a turbo onto a lawnmower if you had the time, knowledge and money. But this isn't a simple, straightforward modification. You need to be...
How long does it take to change oil pan gasket on a 05 Envoy Denali?
Hi and thanks for contacting YourMechanic. It takes the dealer about 1 hour and 25 minutes to replace the oil pan gasket. However, it all depends on what type of experience the person has in removing the pan and gasket...
warning light came on
Hi there: Unfortunately, we don't see a lot of Vauxhall Astra's here in the United States, so it's difficult for us to give you an accurate diagnosis remotely. However, you might want to have a local mechanic complete a check...
My 2010 Ford Ranger is not shifting right
Hi there. When this occurs on this transmission it is almost always due to an internal issue with the transmission. The most common issue I have seen is a failure in the front sprag assembly. When this assembly fails the...
Was driving down the road felt like i hit something car started amoking no lights after driving lights came on now wont start
I have never heard of someone running over a water bottle and it spray all over engine. You were obviously misdirected by someone at the parts store and now you have seized motor from overheating the engine. You most likely...
Related articles
A Buyer’s Guide to the 2012 GMC Sierra Hybrid
When When you buy a truck – even a half-ton truck like a GMC Sierra 1500 – you expect to make a trade-off between hauling capacity and fuel efficiency, right? Well, the designers and engineers at GMC don’t think that...
A Buyer's Guide to the 2012 GMC Yukon XL
When When you want a huge vehicle with plenty of luxury inside, you’re probably going to be happiest with the 2012 GMC Yukon XL. Key Features The 5.3-liter V8 engine on this full-size SUV isn’t surprising, but its fuel economy...
GMC Certified Pre-Owned (CPO) Car Program
Drivers Drivers in the market for a used GMC vehicle may want to check out cars under their certified pre-owned program. Many manufacturers have a certified pre-owned (CPO) program, and each one is set up differently. Read on to learn...
Browse other content
Maintenance
Cities