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Understanding the GMC Oil Life System and Service Indicator Lights

Understanding GMC Service Indicator Lights - view of a GMC instrument panel with warning light on

Performing all scheduled and recommended maintenance on your GMC vehicle is imperative to keep it running well so you can avoid the many untimely, inconvenient, and possibly expensive repairs that come from neglect. Luckily, the days of the standardized manual maintenance schedule are coming to an end.

Smart technology, like the Oil Life System (OLS) system from General Motors (GM), automatically monitors the oil life in your vehicle using an advanced algorithm-driven, on-board computer system that alerts owners when it’s time for an oil change, so they can address the issue promptly and without hassle. When the service light is triggered, such as the “CHANGE ENGINE OIL SOON” light, all the owner has to do is schedule an appointment with a trusted mechanic, take the vehicle in for servicing, and a mechanic will take care of the rest; it’s that simple.

How the GMC Oil Life System (OLS) system works and what to expect

The GMC Oil Life System (OLS) system is not a simple oil quality sensor, but a software-based, algorithm-driven device that takes into account various operating conditions of the engine to determine when the oil needs changing. Certain driving habits can affect the life of the oil, as well as driving conditions such as temperature and driving terrain. Lighter, more moderate driving conditions and temperatures will require less frequent oil changes and maintenance, while more severe driving conditions will require more frequent oil changes and maintenance. Read the table below to see how the OLS system determines oil life: Understanding GMC Service Indicator Lights - HOW DRIVING CONDITIONS AFFECT THE ENGINE OIL LIFE OF A GMC

  • Note: Engine oil life is dependent not only on the factors listed above, but also your vehicle’s model, year, and type of oil that is recommended. Check your owner’s manual for more information about what oil is recommended for your vehicle, and don’t hesitate to get in touch with one of our experienced professionals for advice.

The oil life meter is located on the information display on the dashboard, and will count down from 100% oil life to 0% oil life as you continue to drive the vehicle; at a certain point, the computer will trigger a reminder for you to “CHANGE ENGINE OIL SOON.” Around the 15% oil life threshold, the computer will remind you, giving you ample time to plan ahead to have your vehicle serviced. It is important not to wait to have your vehicle serviced, especially once the indicator reads 0% oil life. If you do wait and servicing is overdue, you risk severe damage to the engine which could leave you stranded or worse. GM recommends that an oil change should be completed within two fuel tank fill-ups from when the first message was displayed, or within 600 miles. Additionally, GMC vehicles - like most other vehicles - require an oil change at least once a year, whether the vehicle is seldom driven in short distances, or is a Garage Queen. If the Oil Life System has not triggered on your GMC for a year or more, take your vehicle in for servicing as soon as possible.

The following table outlines what the information on your dashboard means when the engine oil reaches a certain level of usage: Understanding GMC Service Indicator Lights - WHEN TO CHANGE THE ENGINE OIL IN A GMC

When your vehicle is ready for an oil change, GM has a standard list of inspection for servicing your GMC: Understanding GMC Service Indicator Lights - RECOMMENDED MAINTENANCE SCHEDULES FOR A GMC

GMC also recommends these scheduled maintenance items throughout the life of the vehicle: Understanding GMC Service Indicator Lights - ADDITIONAL RECOMMENDED SERVICES BY MILEAGE FOR A GMC 1 Understanding GMC Service Indicator Lights - ADDITIONAL RECOMMENDED SERVICES BY MILEAGE FOR A GMC 2

After your oil change and servicing is complete, you might need to reset the OLS system in your GMC. Some servicers will neglect to do this, which can lead to premature and unnecessary service light triggers. There are many different ways this light can be reset depending on your model and year. Consult the owner’s manual on how to do this for your GMC.

While the engine oil percentages are calculated according to an algorithm that takes into account driving styles and other specific driving conditions, other maintenance information is based on standard time tables like in old-school maintenance schedules, located in the owner’s manual. This does not mean GMC drivers should ignore such alerts. Proper maintenance service will greatly extend the life of a vehicle, ensuring it is reliable, safe to drive, covered by the manufacturer’s warranty, and it also provides a greater resale value. Such maintenance tasks should always be performed by a qualified technician. If you have any doubts as to what the GMC Oil Life System (OLS) system means or what services your vehicle may need, do not hesitate to contact our experienced professionals for advice.

If your GMC’s Oil Life System (OLS) system is indicating that your vehicle is ready for servicing, have it checked out by a certified mechanic, such as one from YourMechanic. Click here, choose your vehicle and service or service package, and book an appointment with us today. One of our certified mechanics will come to your home or office to service your vehicle.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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