Engine Oil - The lifeblood of your engine
Most people know that engine oil provides protection against friction by creating a thin barrier of oil between the moving parts. But engine oil does more than reduce friction and prevent wear and damage. Did you know that oil also helps keep your engine clean? Dust and dirt that may have slipped by the air filter, along with contaminants produced during the combustion process are captured and retained by the engine oil. The oil filter removes the larger particles as the oil passes through it, but the oil still retains and continues to collect contaminants during its useful life. This is why engine oil is light in color when it goes in and very dark in color when it is removed and replaced. Since engine oil has a limited capacity to hold these contaminants, by not changing the oil on your Buick GMC at the scheduled intervals, those un-trapped contaminants could cause premature wear to engine components, or settle in the engine and oil pan in what is commonly referred to as sludge.
In addition to lubricating and helping to remove dirt, engine oil also helps keep the engine run cool. As oil circulates through the engine it rises in temperature, and carries that heat to the oil pan (which is exposed to a constant air flow when your Buick GMC is moving which helps dissipate the heat away from the engine. Some heavy duty vehicles may use an oil cooler, mounted behind the front grill near the radiator to further help reduce the heat transferred by engine oil.
When do I need to change the oil in my vehicle?
Your owner’s manual will have the oil change intervals recommended by the manufacturer. The type of driving you do may require you to change your oil at more frequent intervals. For example: If you carry heavy loads on a regular basis or do a lot of stop and go driving, the engine oil will be less likely to dissipate the heat it is carrying, leading to a quicker breakdown of it's protective qualities.
What type of Oil is right for my car or truck?
Your Buick or GMC owner’s manual will not only list the recommended intervals for changing your oil, but will list the recommended "weight" of oil to use. The numbers on the bottle of oil are often referred to as the "weight" of the oil. But what does this mean? Many cars on the road today use SAE 5W-30 engine oil. The acronym "SAE" stands for Society of Automotive Engineers. Think of this as a bunch of smart people in white lab coats who set the standards that motor oil must meet for viscosity. Think of viscosity as the thickness of oil, which will determine how well it flows through an engine under various conditions. So for engine oil rated at 5W-30, the "5" is the cold or winter weight. When oil is cold, it is thicker (think of cold syrup versus hot syrup) and will be more difficult to move through the engine. Engine oils are designed to have a thinner viscosity when cold, thus a "5" rating for this particular oil. Lower viscosity engine oil not only flows more readily through a cold engine, it helps improve fuel economy. The second number of the oil weight "30" is the weight of the oil when hot. Motor oils are designed to get thicker as they heat up to ensure proper engine protection. If you are unsure of which engine oil is best for your car or truck, check with your certified Buick GMC technician.