FAQ

General Information

Every batch at Pakistan Lubricants Pvt.Ltd. goes through the following quality checks before it goes down to the filling lines:

At what interval should I change the oil in my car?

You should follow the change interval as recommended in the owner’s manual. A good general rule is to change the oil every 5000 km, or every six (6) months whichever comes first.

What does the "W" mean in 15W40?

The "W" stands for winter, and designates that the oil is suitable for colder climates.

Is Master Oil equal in quality to the oil marketed by the multinational oil companies?

Yes, it is the same basic oil that is sold by the multinational oil companies. The only difference is the label, and the price which is usually lower than the international brands.

What does oil do?

Whether it’s in the engine or around the gears, the purpose of oil is to reduce the friction between two metal surfaces. It does this by sticking to each surface and forming a thin film that keeps the two metal components apart. The parts effectively 'float' on a thin film of oil which stops metal to metal contact reduces friction, heat and wear. The quality and performance of oil is a measure of its ability to perform these functions over a long period of time thereby increasing the reliability and performance of the engine components being lubricated.

Which oil do I need for my car?

This is an important question as the correct oil specification will have a significant effect on the performance, reliability and fuel economy of your vehicle. Lubricants are becoming more and more complicated and specific to particular engine types. You need to use the correct viscosity, match the industry standard and follow the manufacturer specifications. Selecting the wrong oil can cause major engine damage and reduce fuel economy, adding to running costs. Using cheap low quality oil is a false economy. Contact Master Oil to find out about the correct engine oil for your vehicle.

What does the 'viscosity' of an oil mean?

Viscosity is an important criterion of any lubricating oil. It is a measure of a fluid’s thickness or resistance to flow. For example, honey is thick and water is thin, so honey has a higher viscosity than water. Oil viscosity needs to suit the right ambient temperatures. If it’s too thick when the engine is cold, it won’t move around the engine. And if it becomes too thin when the engine is hot, it won’t give the right protection to the engine parts.

Optimizing an oil’s viscosity, or thickness, helps maximize energy efficiency while avoiding component wear.

Viscosity modifiers increase the viscosity of your oil at high temperature but have little effect on low-temperature viscosity. These enable your oil to flow properly when cold and also to remain thick enough to protect your engine components at high temperatures.

Lower-viscosity grade of oil such as MASTER PLUS 500(15W-40) makes it easier for your engine to start from cold because they present less resistance to moving parts and hence take less power from your engine. This also means that you get enhanced fuel economy.

What are performance additives?

Performance additives give extra protection to the base oil and enable it to protect and clean your engine, helping it to work harder for longer. They come in several kinds that must be carefully selected and blended to give top-class performance:

  • Detergents keep your engine clean and neutralize the corrosive acids that form as fuel is burned.
  • Dispersants remove soot and sludge and hold it in the oil to prevent blockages. This dirt can then be removed from your engine at the next oil change.
  • Anti-wear additives protect your engine by forming a chemical layer between the moving parts. These additives are particularly important when motoring with high loads or during engine start-up.
  • Antioxidants help to delay the natural degradation of your motor oil, hence protecting your engine more effectively for longer.
  • Friction modifiers reduce the drag between moving parts to increase fuel economy.
  • Anti-rust additives are essential elements that prevent engine corrosion.

What is Multi-grade oil?

Before the 1960s, all oils were Mono-grade. Multi-grade oils have a designation in the format 20w50 for example. Multi-grade oil was made possible by the use of polymers that expand as they get hotter. Therefore multi-grade oil can have the viscosity of an SAE20 when it is cold and the viscosity of an SAE50 when hot. This removes the necessity to change from thin oil in the winter to thicker oil in the summer, and maintains the best protection for the engine over a wide range of running temperatures. The 20w number is the cold viscosity and the 50 number is the viscosity at 100°C.

Do I need different engine oil for diesel and petrol engines?

Generally the answer is yes for older vehicles, as diesel engine oils have higher detergency levels. It is important to refer to your vehicle manufacturer’s handbook to establish exactly which specification of oil is required. This is vital if your car has extended service intervals and you are still within the warranty period. New vehicles are designed in a way that allows the same oil to be used whether the engine runs on petrol or diesel.

Does motor oil expire? How long does motor oil generally last?

Master Oil does not have a documented expiration date. Under optimal conditions, the product is stable for an extended period of time and can be used as long as the American Petroleum Institute (API) rating on the label continues to meet or exceed the requirements listed in your owner's manual. If the rating is still current, shake the container before use to blend any additives that may have settled.

Does motor oil ever wear out or does it just get dirty?

Motor oil breaks down with mileage and time - the oil additives weaken as the engine oil is used. Dirt can be a factor as well. Changing motor oil on a regular basis will eliminate these factors.

Are conventional motor oils natural, unprocessed products?

The base oils used in conventional motor oils come from a natural source and are then put through a hydrocarbon process in which the additives are blended.

Can I use motor oil in a manual transmission?

If a manual transmission application does not call for the use of motor oil, it is strongly recommended not to use motor oil. Follow the owner's manual requirements for the correct fluid to use for your particular application.

Are all brands of motor oil basically the same?

All brands of motor oil are not the same. Base oils, additives, etc., can be different from one brand to the next. Master Oil is the only product in Pakistan using imported Group II base oils that extends the operating life of the lubricant resulting in less frequent oil changes.

Is switching motor oil brands harmful to my engine?

No. Switching brands is not harmful to your engine since all motor oil manufacturers must meet the same industry standards for performance and compatibility. However, make sure you follow the recommendations provided in your owner's manual for viscosity and API category.

Do I have to change my vehicle's oil filter with every oil change?

Yes. Master Oil recommends replacing the filter every time your vehicle receives an oil change by following the oil change frequency recommendations in your vehicle's owner's manual. This eliminates any risk of contaminants trapped by the oil filter (e.g., dirt) from re-entering the oil.

Is the bulk oil that is put in my vehicle during an oil change different than bottled oil?

Consumers may believe that bulk oil is of lower quality than packaged product because the price is generally less expensive. However, with Master Oil, our bulk oil is the same high quality as our packaged product. The only difference is the size of the container—and the cost savings you realize in paying for one large container instead of multiple liter bottles.

Can motor oil significantly improve horsepower?

Yes. Friction modifiers and additives help achieve this.

What are "severe" conditions?

Severe conditions include stop and go driving, consistent idling, pulling and towing, etc.

If I don't drive in severe conditions can I change my oil less often?

Your owner's manual should provide different oil change intervals for regular driving and severe driving applications.

Is it a good idea to let your car warm up (idle)?

In cold temperatures, letting your car to idle for 2-3 minutes allows the oil to lubricate the engine parts thoroughly before the RPM's are increased.

If owner’s manual states my car requires API SF quality oil, I can’t use API SM quality.

Using motor oil that meets the automobile manufacturer’s warranty requirements is a key factor in developing repeat customers and safeguarding against unhappy customers with damaged engines. With all the changes in engine designs and oil formulations, determining which engine warranty requirements a given oil meets can be a frustrating experience.

The API engine oil classification system is divided into two major categories. The “S” category designates oils for gasoline passenger car engines, and the “C” category designates oils for diesel-powered commercial truck engines. The “S” series is composed of SA, SB, SC, SD, SE, SF, SG, SH, SJ, SL and SM. SM oils provide higher levels of performance than all the other “S” oils. Oils labeled SM can be used in older engines that once required older API categories.

Does the wrong oil cause the dipstick to rust?

No. Generally, rusting of engine parts indicates neglected maintenance or a severe-service environment that requires more frequent oil-change intervals. All high-quality motor oils are formulated to help protect against rust and corrosion. However, to maintain that protection, the oil and filter must be changed according to the recommended maintenance intervals.

I heard that when motor oil becomes dark, that means it's time to change it. Is this true?


This is not a true oil change tip. You cannot determine the life of motor oil by looking at its appearance since it may change color for several reasons. To ensure the best quality product, the best oil change tip is to always follow the owner's manual guidelines for oil change intervals.

 If Oil turns dark or black quickly does that means oil is not good?

Nothing could be further from the truth. If the oil is doing its job of cleaning the engine, then it should be dirty when it is drained. Master Oil will start looking dirty a short time after it is put to use. In the case of diesel engines, the oil may look dirty within a few hours of operation. These are signs that the motor oil is doing its job of keeping soot, dirt and other combustion contaminants in suspension to be carried to the filter or removed from the crankcase when the oil is changed. Master Oil products have been formulated to hold these contaminants in suspension until they can be removed with an oil and filter change.

Is Thicker motor oil better for the engine and does it increase engine life?

Instead of talking about why thicker oils are not ideal, let’s talk about why thinner oils are the preferred choice. The main reason vehicle manufacturers recommend thinner or lighter viscosity grades of motor oil is because a gain in fuel economy may be achieved with lower viscosity oil in an engine designed for the lower viscosity oil. Lower viscosity oil may help reduce internal engine friction because it takes less energy to pump the thinner oil throughout the small passages inside an engine. Any fuel mileage improvement associated with a lubricant would be good for them, and lighter viscosity grade motor oil will make a difference.

A thinner motor oil is also essential for easy starting, particularly in cold weather, and for proper lubrication once the engine starts. Thinner oils enable more fuel economy than thicker oils; this is why OEMs specify them. Thinner oils, such as SAE 5W-30, will flow faster than heavier motor oils during start-up and initial engine operation, and will help protect the engine. The viscosity grade(s) recommended by the vehicle manufacturer depends somewhat on engine design. Engine manufacturers have spent considerable time and expense experimenting with different viscosity grades and have indicated in the owner's manual the grades they feel will best protect the engine at specific temperatures. While one manufacturer's engine may require an SAE 10W-30, another manufacturer's engine may require an SAE 5W-20 viscosity grade. This is likely due to different tolerances within the engine or other engine design factors.