Your GMC is equipped with the latest technology and advanced parts. So when it comes to maintenance, your vehicle deserves the same level of expert care. Below you’ll find answers to some frequently asked questions about maintaining your GMC.
Q: What makes GMC Certified Service technicians different?
A: From oil changes to engine replacements, these automotive experts, nationwide, are trained to care for your vehicle’s special needs, undergoing 1 million hours of instruction annually. They use the latest and most advanced diagnostic equipment available. Both ACDelco and Genuine GM Parts are tested for performance and reliability. So no matter what kind of vehicle you own, trust it to the Certified Service technicians at your GMC dealer.
Q: How can I be sure I’m having my vehicle maintenance performed at the right time?
A: GMC Certified Service is your one-stop shop for everything maintenance related. To learn about your vehicle’s specific maintenance schedule, when to get your oil changed, brake service, and much more, download your GMC Owner’s Manual. It’s that simple. You can also visit the GMC Owner Center anytime to track your service history, view your Owner’s Manual, watch how-to videos, check your warranty status, and more!
OIL CHANGE QUESTIONS
Q: What do I need to do when my “Change Engine Oil Soon” message displays?
A: When the “Change Engine Oil Soon” message displays oil change service is necessary for the vehicle as soon as possible, within the next 600 miles.
If driving under the best conditions, the Engine Oil Life System might not indicate the need for vehicle service for more than a year. The motor oil and filter must be changed at least once a year and the Engine Oil Life System must be reset. Your GMC dealer has trained service technicians who will perform this work and reset the system. Click here to schedule service.
Q: How can I be sure to get the correct type of motor oil for my vehicle?
A: Consult your vehicle Owner’s Manual or visit the Certified Service experts at your GMC dealer to be sure you get the proper oil for your vehicle. For 2011 or newer vehicles, dexos1® Synthetic Blend is the recommended oil specification (dexos1® for gasoline engines, dexos2® for light-duty diesel engines, 15W40 CJ-4 for Duramax diesel engines). Advantages of dexos1® Synthetic Blend over conventional motor oil include improved oil performance and protection, increased piston cleanliness, reduced oil consumption, and greater viscosity control.
Q: I’ve heard that I should change my oil every 3,000 miles. Is that still true?
A: The majority of today’s GMC vehicles are equipped with the Engine Oil Life System, which has made the 3,000-mile oil change obsolete. Depending on the age of the vehicle, driving habits, and road conditions, vehicles with today’s advanced engines can go much longer than 3,000 miles between oil changes. Always be sure to check your engine oil level regularly, even with an Engine Oil Life System.
Q: I have a 2011 or newer GMC. When should I get my tires rotated?
A: Beginning with the 2011 model year, GMC owners are advised to see their dealer for a tire rotation every 7,500 miles as part of a newly revised maintenance schedule.
Q: Why is tire rotation so important?
A: Each tire on a vehicle performs a different task, causing them to wear at different rates. Regular tire rotation allows tires to wear evenly, maximizing tire life and allowing tires to be replaced in sets of four, which is preferable.
Q: I’ve heard that the first tire rotation on my new GMC is the most important. Why is that?
A: Irregular tread wear occurs fastest when tires are new and at full tread depth, thus the first tire rotation has been found to be of the greatest importance.
Q: Is it OK to rotate my tires earlier than 7,500 miles on a 2011 model-year vehicle and newer?
A: Yes, it is OK, particularly if you notice signs of irregular tire wear.
Q: If I have an older GMC vehicle—for example, model year 2000—does the 7,500-mile tire rotation recommendation still apply?
A: While the 2000 Owner’s Manual recommends a range of 5,000 to 8,000 miles, the 7,500-mile tire rotation interval is a good rule of thumb. However, any time you notice unusual wear, you should rotate your tires as soon as possible. Check to ensure that your GMC is properly aligned and that there are no suspension issues causing irregular tire wear.
Q: My GMC has an Engine Oil Life System. Can I have my tires rotated when I get my motor oil changed?
A: Yes. For your convenience, you can have both the tire rotation and oil change service completed at the same time, as long as you are rotating the tires approximately every 7,500 miles.
Q: Why is tire pressure important?
A: Improperly inflated tires are a leading cause of tire failure. Proper tire pressure helps a tire have optimum tread contact with the road, which improves traction and braking and reduces tire wear—this is especially important when hauling cargo or towing. Underinflated tires generate heat, which is the tire’s worst enemy, so maintaining the right amount of air keeps temperatures where they should be.
Q: How often should I check my tire pressure?
A: Checking your tire pressure once a month is a good guideline. For specific information on your vehicle, refer to your GMC Owner’s Manual. Be sure the tires are cold (not driven for three hours or driven less than one mile), and don’t forget to check your spare tire. Use a good-quality tire gauge to check your tire pressure—don’t try to “eyeball” tires because they can look fine even when they are underinflated. Remember that tires can lose air pressure in cold weather.
Q: How will I know when I need new tires?
A: You’ll need new tires when the tread wear indicators—called wear bars—appear. These wear bars look like narrow strips of smooth rubber across the tread and appear when it’s time to replace your tires. If you can see three or more tread wear indicators around the tire, you should replace your tires. Other ways to know when you need to replace your tires include cord or fabric showing through the rubber, cracks or cuts in the tread or sidewall deep enough to show cord or fabric, bulges or splits in the tire, and punctures or damage that cannot be repaired correctly.
If you have questions about whether your tires need replacing, see the experts at your nearest GMC dealer.
Q: There are a lot of places that sell tires. Where should I go to get the right tires for my GMC at the right price?
A: Certified Service expert technicians at your dealership can recommend the tires that are right for your GMC, your driving habits, and your budget. Also, participating dealers offer a tire price match guarantee, so if you find the same tires at a better price within 30 days of purchase, they’ll refund the difference.‡Click here for additional details.
I definitely need new tires. What now?
A: You can start searching for new tires right now with our Tire Finder Tool. It’s a quick and easy way to find tires for any vehicle—including your GMC. Once you’ve selected the right tires, our Certified Service expert technicians can handle all your tire needs at your scheduled appointment.
AUTO BATTERY QUESTIONS
Q: Why won’t my car start?
A: There are numerous reasons why a vehicle won’t start. If it’s related to the battery, the starter will generally not crank the engine. This is the telltale “click, click, click” when you turn the key. This could be an alternator not charging the battery properly, a loose battery or starter cable, or a battery that needs to be replaced.
Q: Do I need to charge my auto battery after I jump-start my vehicle?
A: In most instances, normal driving will recharge the battery, unless there is an issue with the vehicle. If your vehicle does not start after driving it, it’s recommended that you take your vehicle to your nearest Certified Service experts to have a diagnosis performed.
Q: What are the main causes of auto battery failure?
A: Batteries wear out over time, but there are also issues that impact battery failure, for example, unusual “parasitic drains” such as adding accessories but not properly grounding them, infrequent startup, and discharged batteries freezing at 32 degrees Fahrenheit.
Q: What should I consider when buying an auto battery?
A: ACDelco recommends the right balance of Cold Cranking Amps (CCA) and Reserve Capacity (RC). A higher CCA battery will not start your car faster. This is due to gear reduction starters, lower viscosity oils, fuel injection, etc. The average car cranks no more than 3 seconds and as a result does not need more CCA than what the vehicle manufacturer recommends. With the addition of vehicle electronics, RC is becoming more important. Select a battery that has the right amount of CCA, found in your Owner’s Manual, and as much RC as you can.
Q: What kind of preventative maintenance can I perform for my auto battery?
A: The best thing that you can do is have your Certified Service technician perform a conductance test on your battery when you get your oil changed. This helps to monitor the status of the battery and helps prevent you from being in a situation where your vehicle won’t start.
WIPER BLADE QUESTIONS
Q: How do I know when my wiper blades need changing?
A: A blade’s natural rubber deteriorates after about 6 months, which is why it’s recommended that you replace your blades on a semi-annual basis. Streaking, squeaking, chattering, skipping, cracks, tears, splits, bent or broken frame, worn rubber, and rounded wiping edge are some common signs that your blades need to be changed.
Q: Even though one of my wiper blades is more worn than the other, should I replace both of my wiper blades?
A: Yes, it is recommended that you replace both. This will ensure your windshield is clear and provide a safer view when driving.
Q: Is there anything I can do to make my blades last longer?
A: The biggest enemy of wiper blades is exposure to sunlight and ozone. There is little that can be done to reduce ozone exposure, but limiting the amount of time your blades are exposed to direct sunlight will help prolong the life of the wiper blade. Clean your windshield and the rubber element of your wiper regularly. Use an ice scraper and defroster to clear ice from your windshield, not your wipers. Pull your wipers away from the windshield in winter to prevent ice buildup from sticking to the windshield.
Q: What can be used to clean wiper blades?
A: It is recommended to use hot, soapy water or another nonabrasive liquid.
Q: Why is my wiper blade streaking?
A: Streaking is caused by worn blades. A blade’s natural rubber deteriorates after about 6 months.
Q: How easy it is to replace wipers?
A: Wiper replacement is easy, and instructions are typically included with your wipers. If purchased at your GMC dealer, the Certified Service experts will install them for you.
Q: Are all wipers designed the same way?
A: No, there are lots of different designs: beam, conventional, and winter are the most common.
Q: What is the difference between conventional and beam blades?
A: Beam blades feature a frameless design that helps them conform to the shape of the windshield and maintain uniform pressure to keep your view especially clear. They also feature a low-profile design that improves aerodynamics and enhances style. Conventional blades feature a metal frame design. This design has less pressure points and does not have uniform pressure across the windshield. (Beam blades have an infinite amount of pressure points.)
Q: My car came with conventional blades. Can I use beam blades instead?
A: Of course, you can upgrade your conventional blades quickly and easily to the latest technology in beam blades.
Q: How do I know when I need new brakes?
A: Brake pads are equipped with wear indicators that produce a squealing noise when the brakes are almost worn out. The noise may be present with or without the brake pedal applied, but when noise is heard from the wear indicator, the brake pads should be replaced as soon as possible. Wear indicators are set to create noise when there is around 2 mm of brake pad friction material thickness remaining. In the case of assessing pad wear through inspection, pads should be replaced at or before 2 mm thickness is reached.
Brake rotors are marked with a “minimum thickness” on the casting (usually 2mm to 3 mm less than the new rotor thickness). Rotors should be replaced before they reach this minimum thickness and should not be turned below this.
Q: Must I always turn or replace my rotors when changing my pads?
A: No. If there are no conditions such as pedal pulsation or steering-wheel vibration during braking, and the brake rotor is at least 1 mm thicker than the discard thickness, then it does not need to be turned or replaced.
Q: Which is better, cross-drilled or slotted rotors?
A: Both cross-drilled and slotted rotors have a similar effect on brake friction. Comparative testing by General Motors shows that friction levels of cross-drilled rotors are 5-10% lower at cold temperatures (relative to non-drilled or slotted rotors), but remain more stable with increasing temperatures (less fade) and end up with 5-10% higher friction at high temperatures (752-1112 degrees F). This is true for both slotted and drilled rotors.
General Motors uses predominantly slotted rotors on applications requiring it in order to maximize the service life of the rotor. Cross-drilled rotors have been used in the past, mainly on lighter vehicles where there is less risk of cracking.
Q: Why does my brake pedal pulse?
A: Brake-pedal pulsation and other conditions such as steering-wheel shaking while braking are caused by thickness variation in the brake rotor. When a thicker spot of the rotor rotates through the caliper, it pushes back against brake fluid, which can be felt at the brake pedal. The brake fluid and pedal then relax again as the thick spot exits the caliper. This process produces pedal pulsation and “brake torque variation,” which can shake the steering wheel and seats. Brake pulsation is not caused by warping of the disc. However, distortion of the disc due to excessive temperatures or improper installation and torqueing of the wheels can lead to brake rotor thickness variation over time. Brake-pedal pulsation is corrected by turning and/or replacing the brake rotors to eliminate the thickness variation.
Q: Why do my brakes squeal? How can I stop it?
A: Brake squeal is caused by the high-frequency vibration of brake components (rotor, calipers, and/or pads) in response to excitation from the brake friction process. A significant amount of time and engineering goes into eliminating brake squeal from original equipment brake components. Brake components are engineered as a complete system—factory-original performance can only be assured when using original equipment brake pads and rotors. When brake squeal occurs, there may be damage or excessive wear on one or more components affecting noise, including the brake pads, the noise-damping shim that is bonded to the brake pad, or the rotor friction surface.
In addition, it should be recognized that high-performance and track-capable brake systems using high-performance pad materials will always be at higher risk for producing brake squeal noise, even when no damage to the components is present.
Q: How long will my pads last?
A: Pad life depends on driving habits, vehicle usage, and operating environment. Brake systems are designed to provide 20,000 to 25,000 miles of pad life in very severe use (such as heavy-traffic urban areas) and will give 40,000 to 60,000 miles of pad life in average use. Factors that will reduce pad life include frequent heavy braking, elevated temperatures (caused by high-speed braking, driving in mountainous areas), driving with the vehicle heavily loaded, and severe environments such as high-corrosion areas and areas with a lot of road debris and dust.
Q: Do metallic pads eat rotors?
A: Yes. Pads with higher metal content will tend to operate with more abrasive friction, where hard metal particles in the pad interact directly with the brake rotor surface. Use of metallic pads will create more brake dust and will shorten the rotor life. Non-asbestos organic pads (also known as ceramic pads) used on most GM vehicles in North America develop a transfer film, a layer of material on the pad and rotor surface that acts as a cushion (at a microscopic scale) between the pad and rotor, protecting both from abrasive interaction that causes wear.
Q: My brake pads are very dusty. Are all pads dusty?
A: Brake dust can occur to some extent on most brake systems, but it is significantly more noticeable with metallic pads and on high-performance brake systems. Brake dust is a mix of debris from the brake rotor, which is the most significant component, and debris from the brake pads. Pad materials that wear the rotor more aggressively will cause more dust.
Q: Are all brake rotors the same?
A: There are often significant differences between original equipment and aftermarket brake rotors. While brake rotors designed to fit the same vehicle will often be similar in appearance and dimensions, there can be differences in internal cooling vane design, thickness of the brake plates (against which the brake pad rubs), and the grade and material specification of the cast iron. For original equipment brake rotors, significant analysis and testing goes into determining the right geometry to minimize thermal distortion and squeal noise and to maximize cooling. Similar rigor is put into the material selection, which also affects the risk of squeal noise, as well as friction and wear properties.
For additional inquiries regarding product features, parts and accessories, warranties, and much more, please visit our Frequently Asked Questions page.
‡Ad, written estimate, or Internet quote for identical tire(s) from a competing tire retailer/installer located within 100 miles of the dealer required during guarantee period for price match. Offer valid at participating U.S. dealers.