What does oil or Lubricant do ?

The purpose of oil or lubricants 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 metal components apart. The parts effectively ‘float’ on a thin film of oil or lubricant 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.

What does the ‘viscosity’ of an oil mean ?

Viscosity is a measure of the thickness of the oil. The viscosity of engine oil at low and high temperatures is measured on a scale determined by the Society of Automotive Engineers and given a number known as the SAE number. Therefore SAE 30 oil will be thinner than SAE 40.

What is the difference between mineral oil and fully synthetic oil ?

Mineral oil is obtained directly from the crude-oil refining process, whereas synthetic oils are produced by synthesis process which improves its chemical structure. Synthetic oils have better performance than mineral oils at all temperatures, and are more durable. They are more expensive but are higher quality, offer higher performance and longer life.

What are the characteristics and benefits of synthetic oils ?

  • Better oil-flow at low temperatures enabling thinner oils to be manufactured. Thinner oils are required by modern engine designers to help reduce the fuel consumption and emissions
  • Superior lubrication between moving parts, giving better protection thereby reducing wear & tear
  • More stable and less volatile at high temperatures, reducing oil consumption.

What is Semi synthetic oil ?

A semi synthetic oil is a blend of mineral and fully synthetic base oils. The performance, price, quality and durability is between that of a mineral oil and fully synthetic oil. Lower quality semi synthetic oils have very little fully synthetic content and will cause multiple problems in the engine.

Why is synthetic oil more expensive than mineral oil ?

A synthetic oil is produced in a more sophisticated and expensive manufacturing process. A fully synthetic oil does have many performance advantages (see above) which justify the additional cost. Fully synthetic oil allows longer service intervals, reduces oil consumption, extends engine life and contributes to improved fuel consumption – driving running costs down. It is all about quality and performance.

Is synthetic motor oil made in a laboratory ? Is it “fake” oil ?

Synthetic oils are not fake – they are still derived from Petroleum crude. However, synthetic oils use higher base stocks than mineral oils and go through a synthesis process in which all the molecules are made into the same size for a better film strength.

Is it ok to switch back and forth between mineral and synthetic motor oil? Is this true that this causes leaks ?

Switching between synthetic and conventional oil does not cause problems. Because the oils are compatible, you can switch back and forth as often as you like.

Can you mix Mineral and synthetic oils ?

Mixing synthetic and conventional oils will not cause any problems. The oils are compatible with each other.

What are Base Oil groups ?

The industry standard is based on the API Base Oil Classification:
Group I – Conventional Paraffinic Mineral base oils
Group II – Low sulphur Paraffinic and some hydro-cracked (VI below 120) mineral base oils
Group III – Hydro-cracked (VI above 120) synthetic base oils
Group IV – Poly-Alpha-Olefins (PAO) synthetic base oils
Group V – Esters etc.

What is a multigrade oil ?

Before the 1960s, all oils were monograde. Multigrade oils were developed have a designation in the format 20w50. Mulitgrade oil was made possible by the use of polymers, that expand as they get hotter. Therefore a multigrade 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.


What does API mean ?

API is the American Petroleum Institute, which represents America’s oil and natural gas Industry including performance certification for motor oils. Gasoline engine oil categories fall under the ‘S’ (‘Service’) categories e.g. SN, SM, SL. Diesel engine oil categories fall under the ‘C’ (‘Commercial’) categories e.g. CJ-4, CI-4, CG-4. The EC or “Energy conserving” rating applies to gasoline-engine cars and light commercial vehicles. Use of EC oil may result in an overall saving on fuel in the vehicle fleet as a whole.

What does ACEA mean ?

ACEA is the Association des Constructeurs Europeens d’Automobiles, which represents the interests of European car, truck and bus manufacturers. ACEA standards are split into 3 main categories:

  • A/B: – Engine oils for gasoline and light duty diesel engines.
  • C: – Catalyst compatible oils for gasoline and light duty diesel engines with after treatment devices.
  • E: – Heavy duty diesel engine oils.

Each category is further sub-divided with a letter designation e.g. A3/B4, A5/B5, C2, E7.

Which oil do I use in my car ?

The correct oil specification will have a significant effect on the performance, reliability and fuel economy of your vehicle. Oils 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. Please contact CREST Engineer to get the right advice for the use of correct engine oil and gearbox oil for your vehicle.

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.

What does the `W` in 15W-40 engine oil mean ?

The “W” stands for “Winter” and gives the viscosity measured at the lower temperature range.

What is a low SAPS engine oil ?

Low Sulphated Ash, Phosphorus and Sulphur. This type of oil is intended for use as catalyst compatible oil in vehicles with Diesel Particulate Filters (DPF) and Three Way Catalyst (TWC)

What should I look for when choosing an engine oil ?

Care should be taken to select the oil which meets the engine manufacturers requirements usually be means of performance criteria eg ACEA, API or Manufacturer’s standards. Careful note should also be taken of the recommended viscosities.

How does CREST Ultramax and Ecomax Motor Oils compare to Mobil 1 and Castrol Edge ?

CREST Ultramax and Ecomax Motor oils meet and exceed the same performance standards as these two products.

CREST Ultramax oils are Top-performance, high-quality oils formulated with full synthetic base oils and top tier additives to provide an increased level of performance. The CREST Ultramax and Ecomax range of engine oils conform to specifications laid down by the global Automotive manufacturers, such as Mercedes-Benz, BMW, Porsche, Volkswagen, AUDI, Toyota, Honda, Renault-Nissan, Hyundai-Kia, Ford and Opel etc.

Why are synthetic oils more expensive ?

Synthetic engine oils are superior to conventional oils because they help maximize horsepower, improve fuel mileage and provide a smoother, cooler operation for the engine, prolonging engine life. Many vehicle owners feel that the benefits of using a synthetic motor oil are worth the extra cost.

Does using synthetic oil create more sludge ?

No. Synthetic engine oils do not increase the chance of sludge. CREST motor oils are 100% anti-sludge guaranteed.

Does using synthetic oil cause my car to use more oil ?

No. Synthetic engine oils do not increase oil consumption. Infact, the synthetic oils should reduce the oil consumption and top-ups

Does using synthetic oil damage engine seals ?

No. Synthetic motor oils are perfectly safe and compatible for all rubber seals.

I heard that synthetic oil is too thin for use in an older car and creates blow-by and burn-off. Is this true ?

This is only true if the engine is already in a bad condition and the blow-by problem exists prior to using a synthetic engine oil. The synthetic Motor oil will clean the engine deposits, improving the fuel economy.

Do I need to use a different type of oil filter with synthetic oil ?

No. You can use any type of oil filter with a synthetic engine oil.

What does ‘high HTHS’ and ‘low HTHS’ oil mean ?

The current generation engines, being compact are running at very high temperatures. Measuring the viscosity at 100°C was not too representative of the temperatures reached today by the latest generation of engines. Therefore a standard test was introduced to measure viscosity at 150 °C, and under a high shear rate, so as to really examine the ability of the oil. Hence what HTHS (High Temperature, High Shear) viscosity stands for, the “mPa.s” is a unit to measure HTHS viscosity.

The concept exists of High HTHS and Low HTHS: A low HTHS oil has a lower viscosity at high temperature (<3.5 mPa.s) than that of a so-called High HTHS oil (>3.5 mPa.s). This notion is important as it allows for the classification, on the one hand, of fuel economy oils having a low HTHS and, on the other hand, of high protection oils having a high HTHS.

Oil drain intervals

The oil drain interval depends on the frequency of use of your car and also on the type of driving you do.

  • For ordinary daily driving, you should follow the OEM’s recommendations, either in your service hand book or on the in-car display.
  • If you take part in track-days or performance races, you should shorten the oil drain intervals. Our technical desk will be happy to discuss the possibilities according to your usage and driving style.
  • Similarly, if your engine has been modified or tuned, you can no longer follow the OEM’s recommendations. In this case also, you should shorten the period between oil changes. Again our technical desk can give you advice depending on the modifications you made to your car.

Should Engine oil additives/supplements be used ?

The CREST Engine oils are fortified with high performance additives to offer the best engine performance. Any additional additives or supplements used in the engine oil are unnecessary and may even have a negative effect on the engine performance.


Can we use the Car Engine Oil in Motorcycle ?

Most modern 4-stroke motorcycle engines have integrated lubrication system to lubricate the engine, gearbox and clutch. The passenger car engine is designed specifically for the cars and might cause severe damage to the Motorcycle engines.

In a passenger car, the engine is separated from the gearbox and the clutch hence different Oils are used which are specific for each mechanical component. For example, the engine oil in a passenger car can be formulated with a variety of friction modifier additives to achieve fuel economy benefits without causing any compatibility problem with the clutch. The gearbox lubricant is also specifically formulated to resist the very high shearing and contact pressures found when the gears are in operation.

This is why CREST offers specific products for individual applications: whether it’s for your 4-stroke motorcycle or passenger car. By choosing the right product, you’re ensuring that the mechanical components of your bike or car are protected by a dedicated lubricant meeting the technical requirements set out by the Original Equipment Manufacturers.

What are JASO-MA and JASO-MB Standards ?

Japanese Original Equipment Manufacturers (OEMs) are members of the Japanese Automotive Standards Organization, (JASO) who have drawn up specifications to avoid clutch slip problems and require motorcycle oils to have a given level of performance. These are referred to as JASO MA and JASO MB standards. The JASO-MA oil is designed for the 4-Stroke Motorcycle engines with wet-clutch; however the JASO-MB oil is designed for the engine with Dry clutch. The JASO-MB oils are fortified with a special friction modifier to offer improved lubrication.

Why are oil drain intervals shorter for motorcycles compared to cars ?

Unlike with cars, the capacity of motorcycle oil sumps is generally limited given the low overall dimensions of a motorcycle engine. For scooters in particular, their capacity is often less than 1 litre and for some applications dry sumps can also be used. (this is when the oil sump is located remote from the engine).

Given these lower volumes of oil in motorcycles and the increased constraints put on the lubricant, such as higher temperatures, multiple lubrication (engine, gearbox and clutch) and extreme RPM – oil drain intervals are shorter for motorcycles than for cars.

However, we advise that In any event you should always refer to the Instruction / Service recommendations for the correct oil change intervals.

I am using different Oil brand in my Motorcycle. Can I use CREST 4T Oil without damaging my Motorcycle engine ?

4-stroke Motor oils are compatible with each other and can be mixed. You can therefore safely use a Quality CREST Motorcycle Oil in your motorcycle from now on.

I am using a 20W-50 oil in my motorcycle engine. During winters, I hear a cracking sound while starting engine. What should I do ?

Your engine probably operates with hydraulic pushrods. At low temperatures, a 20W or 15W oil is too viscous to ensure the proper operation of such parts. You should therefore use a 10W-40 or 5W-40, depending on the OEM’s recommendations – please refer to your handbook that came with the bike or contact CREST helpdesk for any recommendation.