Engine Oil FAQ

Properly following your oil change schedules and choosing the right engine oil can have a huge effect on your car, from fuel economy, to performance, engine life, and even exhaust emissions. Here are some of the most frequently asked questions about engine oil.

Q: What does the engine oil do?

Engine oil does the following:

• cooling engine hot spots and moving parts

• ensuring that engine parts remain clean

• ensuring leak tightness between engine parts

• protecting the inner surfaces of the engine against corrosion

• distribute helpful additives, such as detergent and dispersant additives, and the additives against corrosion

Q: What are the advantages of choosing a higher quality engine oil?

Good quality oil provides motorists with a number of benefits:

• use of the latest and most advanced lubricant technologies and additives

• easier cold start and reduced wear (20 to 30% of engine wear occurs between startup and the time the engine reaches optimal temperature)

• longer engine life

• fuel savings as a result of reduced friction of moving parts and better engine performance

• improved emissions

Also, modern high efficiency engines have stricter tolerances and greater lubrication needs, which means using a higher quality oil is more important than ever.

Q: Why change the oil?

A: The oil change is an essential operation in maintaining a vehicle in top condition. Lubricants collect particles of internal and external pollution (carbonic matter, particles of worn metals), and these impurities must be removed by changing the oil. Also, older engine oil loses its effectiveness in lubrication because of oxidation, wearing off of important additives, and inevitable mixing with moisture. All of these things can negatively affect the oil's ability to lubricate the engine and protect components from wear and damage, which lead to greater fuel consumption, loss of power and performance, greater smoke emissions, and shorter engine service life.

Q: How often should oil be changed?

A: It is always best to follow your car's recommended oil change interval, as shown in your car's manual or service booklet, or at least once a year, which ever comes first. It is also good practice to check the oil's condition periodically, and if the oil color is a dark brown, or is watery, those are signs that the oil needs changing.

Q: How do I check a car's oil level?

Most cars in the Philippines will have a dipstick in the engine bay. The dipstick pull handle is usually ring-shaped, and color red.

It is recommended to check the oil level before starting the engine, or 10 to 15 minutes after the engine is shut off. When the engine is cold, pull the dipstick out of its tube, and completely wipe the oil off the tip with a clean rag. Then, insert it fully back into the tube, pull it out again, and then read the oil level on the dipstick by checking where the oil mark sits between the "full" and "add" markings. If the oil level is low, add oil until it reaches the proper level between the marks on the dipstick

Never drive with an oil level below the minimum mark on the dipstick. When oil is below this mark, it means that the oil is not enough oil, therefore, this causes more rapid circulation of the fluid and accelerated wear on the oil. It is recommended to check the level regularly every 1,000 km and especially before a long trip.

Q: Does the oil have to be topped up?

A: The engine oil level should be checked regularly to prevent incidents. A small amount of the oil that circulates in the engine is always burnt (an engine in good condition consumes between 0.2 and 0.5 liters of oil every 1,000 kilometers), but successive top-ups are no substitute for an oil change.

Accordingly, it is natural that an engine consumes a small amount of oil, which can be offset by top-ups between oil changes; however, excessive need for top-ups can be an indication of mechanical problems (leaks, etc).

Q: What do the numbers mean on an oil bottle, such as 5W40?

A: Any engine oil that has numbers like these are called multi-grade oils. The numbers indicated on the label are a measure of the oil's viscosity grade at low temperatures (such as in winter) and higher temperatures (such as summer). So an oil that says 5W40 has a viscosity grade of 5 at cold temperatures (W meaning winter) and a grade of 40 in hot temperatures.

Q: What is the difference between Mineral, Semi-Synthetic, and Synthetic oils?

A: Each oil type has different characteristics. Here is a short description of each:

Mineral oils

They are obtained from base oils directly extracted from crude oil and then enriched with chemical additives in order to improve their overall performance.

They are applicable to cars that are only used for everyday trips or journeys outside of an urban environment, and at reasonable speeds.

Semi-synthetic oils

They are a blend of mineral oils and synthetic-based oils. They are well-suited for normal usage in urban environments or high-speed driving for all types of vehicles.

These oils are highly resistant to oxidation and can be recommended for extreme temperature conditions. Oils that use the terms "synthetic-based," "made with synthetic technology," or "uses synthetic technology" are usually semi-synthetic oils, and not fully synthetic.

Synthetic oils

They are obtained through numerous refining processes or in laboratories using high-quality additives. Synthesizing oils in this way has many benefits: the result is a high-performance lubricant that extends the life of your engine, improves engine protection, increases the intervals between oil changes and reduces friction – thus lowering fuel consumption. Synthetic oils are best for vehicles with engines that are subjected to higher RPMs, such as performance cars or heavy duty vehicles.

Q: What are the advantages of using synthetic oils?

Semi-synthetic and synthetic oils are made from non-conventional bases using sophisticated chemical processes which confer special properties to the finished product. First, the high level of viscosity of the base oils used gives the finished lubricant remarkably stable viscosity whatever the temperature. This property is one of its major advantages over mineral oils, made from conventional bases which require a greater number of additives in order to improve viscosity. The stability of lubrication in all temperatures guarantees optimum efficacy in the cold starting phase which is particularly demanding on the engine as well as under conditions of extreme heat. Synthetic-based lubricants show greater resistance to oxidation, which gives them longer effective life thus guaranteeing longer engine life. The use of non-conventional bases, finally, permits the elaboration of more fluid lubricants, without being more volatile; resulting in a reduction of oil consumption.

Q: Which oil should we use in turbocharged vehicles?

A: High quality, fully synthetic oils are recommended for all turbocharged engines. In order to fulfil the lubrication and shaft cooling needs of the turbo-compressor, oil must answer to very strict criteria. The shaft reaches, a very high temperature, due to the proximity of the exhaust gasses, a very high temperature. Oil must lubricate the shaft continuously otherwise the high temperatures would permanently damage it and the temperature would then very rapidly reach very high levels. This is especially true of turbo-diesel engines, which have higher compression ratios and thus higher operating temperatures.

Q: What causes oil pressure to drop?

A: During normal vehicle operation, oil is vital to ensures leak tightness between the combustion chamber and the crankcase. The oil pressure indicator shows how well this is being done.

An unusual drop in oil pressure can result from either lower engine oil viscosity due to dilution by fuel (injector problem or use at low load); too little oil in the lubrication system (due to an oil leak, excess oil consumption, or failure of the oil circulation pump); or even mechanical part wear.