01. What are Lubricants?

A substance introduced between two moving surfaces forming a film that minimizes contact between parts and this reduces wear and heat.

02. What is mineral oil?

It is a lubricant that its main ingredient is oil obtained from refining petroleum.

03. What is synthetic oil?

It is a lubricant that its main ingredient is obtained from chemical reactions done in a laboratory.

04. What do lubricants do?

- Lubricate
- Cool
- Clean components and keep them clean
- Prevent corrosion
- Seal the combustion chamber

05. What is viscosity?

It is a measure of the resistance of an oil to flow.
It is defined as the resistance of a fluid to its own movement. As viscosity decreases, the greater will be its ability to flow.
Oil viscosity categories are obtained experimentally in a Laboratory using an instrument called a VISCOMETER. It is a standard test which measures the time that a certain fluid takes to drain through a small tube (capillary tube) at a constant temperature.
The temperature of the test must be constant because viscosity is a property that changes according to variations in temperature. The higher the temperature, the greater will be the ability to flow, and in low temperatures, the fluid becomes more resistant to flow due to the increase of its viscosity.

06. Why do various levels of viscosity exist?

They exist to meet the various specifications of the vehicle and equipment manufacturers.

07. What is multi-grade oil?

It is an oil designed for various viscosity ranges.
This means that in low or high temperatures the fluidity as well as the lubrication power is maintained.

08. Is it better to use SAE 15W-40 or SAE 40 oil?

The best is to use SAE 15W-40 because it is designed for a greater viscosity range, maintaining the lubrication efficiency at various temperature conditions.

09. Why do we need to change the engine's oil?

After using it for some time, the oil's additives deteriorate physically and chemically or combine with other chemical substances. Consequently, the oil loses its efficiency and this increases the heat and wear on the components.

10. When do I have to change the oil?

It is best to always follow the service manual's recommendations for your vehicle..

11. What can happen to the engine if you don't change your oil at the recommended change period?

After the change period recommended in the Operator's Manual is past, the lubrication and protection capacity decreases immensely causing excessive wear on the components and this lowers the engine's operating life.

12. Which problems can too much or too little oil cause on the engine?

In the case of too much oil, it is burnt up and pollutes the environment.
In the case of too little, the lubrication and cooling is lowered causing various damages to the engine and can even burn it.

13. What is the correct way to check the oil level?

1. Park the vehicle on level ground.
2. Turn off the engine.
3. Wait at least 5 minutes. The best is to check when the engine is cold.
4. Measure the oil level (dipstick).
- The ideal level is between the minimum and maximum marks shown on the dipstick.

14. When should I add oil to the engine?

Always when the oil level is close or below the minimum mark on the dipstick and the change period has not come yet.
Normally, the engine consumes little amounts of oil when it is on.
If you constantly and in significant volumes need to add more oil, you should check if there are leaks or excessive wear on the engine components.

15. If I just add oil and never change it, will it cause damage to the engine?

Yes, the waste created by engine use accumulates, which contaminates the oil and accelerates wear. When you add more oil, it becomes contaminated by the waste already in the old oil and loses its lubrication and cooling effect. As a consequence, the engine oil filter becomes clogged and this lowers the circulation and raises even more the operating temperature. All of this in the end can permanently damage the engine because of lubrication problems.

16. Can you mix different brands or types of oil?

It is not recommended to mix different brands or types of oil since there can be an incompatibility between the additives used in the product's formula and can cause lubrication efficiency loss.

17. Can I add additives to the oil?

No, oils are designed to meet the engine's required performance according to the manufacturer. All of the necessary additives are already adequately contained in the oil. If you add more additives, they can jeopardize the lubrication efficiency and even the vehicle's engine.

18. Why does the engine oil become dark after using it for some time?

The engine oil becomes dark because the detergent/dispersant additive removes the carbon waste formed in the engine and remains in suspension.

19. Can I know if the oil is in good usable condition or not by just touching it?

No, because the real oil conditions can only be determined by an analysis of the product in a laboratory.

20. What is the SAE classification?

The SAE (Society of Automotive Engineers) classifies oils according to viscosity ranges in two grades: one for low temperatures (0W ~ 25W) where the letter W means winter and the other for high temperatures (20 ~ 60). Look at the graphs below:

21. What is the API classification?

The API (American Petroleum Institute) classifies automotive oil by performance and viscosity measured in low and high temperatures to determine the oil's working range.
(API CI– 4 Lotus Specification)

22. What is the ACEA classification?

ACEA - (Association des Constructeurs Européens d`Automobiles) European Automobile Manufacturers Association
This standard divides Gas and Diesel (light and heavy) engines into three categories:
-Category A – Gas Engines
-Category B – Light – Diesel Engines
-Category E – Heavy – Diesel Engines
(Lotus ACEA E7 specification)

23. How do I know the oil's classification?

The label found on the oil's package always has the product's specifications. See the example below:

24. Can I use API CI-4 oil for more time than the API CH-4 oil?

The fact that the oil is classified as API CI-4 or CH-4 does not mean that it has a longer or shorter change period. In the case of Lotus, the change interval is the same for either API CH-4 or API CI-4. But if you use the API CI-4 oil, the vehicle's engine will have superior lubrication and protection and therefore will increase its operating life and performance.

25. What do the acronyms (API, ACEA, JASO, and NMMA) that come on the oil package mean? What do they mean in relation to the product's performance?

These are acronyms to international entities that are responsible to elaborate a series of standards (based on specific tests) to classify oils according to their use. In this way, the consumer can identify if the oil meets his equipment's demands by looking in its manual. These acronyms mean the following:
SAE - Society of Automotive Engineers.
It is the oldest classification for automotive oil, defining viscosity ranges without taking into consideration the requirements of performance. It has a classification for engine oil and another specifically for transmission fluid. For more information, go to "What do the numbers (20W/40, 50, etc.) that show on the oil packages mean?".

API – American Petroleum Institute
This is the group that together with ASTM (American Society for Testing and Materials) elaborated specifications that define performance categories to which oils must comply. Customers can use these specifications as a guide to buy what they want. For passenger cars, for example, we have the API categories SL, SJ, SH, SG, etc. The “S” in these acronyms means Service Station and the other letter defines the performance. The first category was the API SA, which has been obsolete for a long time. It consisted of a pure mineral oil without any additives. With the development of engines, oil went changing by the addition of additives to meet the engine manufacturer's demands such as protection against wear and corrosion, reducing emissions, reducing the formation of deposits, etc. Today the API SL category is the latest technology. In the case of diesel engines, the categories are: API CI-C4, CH-4, CG-4, CF, etc. The “C” means Commercial. The API also classifies oil for two-stroke engines, transmission fluids, and gear oil.

ACEA - Association des Constructeurs Européens de l´Automobile (former CCMC)
It is a European classification which associates some tests of the API classification, European engine (Volkswagen, Peugeot, Mercedes Benz, etc.) tests, and laboratory tests.

JASO – Japanese Automobile Standards Organization
It defines specifications to classify oil for two-stroke engines (FA, FB and FC, in increasing order of performance).

NMMA- National Marine Manufacturers Association
It replaced the BIA (Boating Industry Association) and today classifies oils that meet its demands with the TC-W (Two Cycle Water) acronym, only applicable to two-stroke boat engines. Today there are TC-W3 category oils because the older categories are not being used.

26. In relation to automotive gearbox oil, what is the difference of specifications between API GL-4 and GL-5? Is there any problem to use GL-5 instead of GL-4?

The API GL-4 specification is designed to be used for hypoid gears in passenger cars and other automotive equipment operating under high velocity and low torque conditions or vice-versa.
The API GL-5 specification is also designed to be used for hypoid gears operating under high velocity and instant load (chock) conditions, which are situations found in truck gearboxes and in rear axles (differentials).
Using API GL-5 oil in the transmission instead of GL-4 will create engaging problems and "scratching" during gear switching, thus jeopardizing the gearbox's operating life. This problem occurs because of the extra additives that the API GL-5 has in relation to the API GL-4 that ends up negatively interfering with the operation of the gear synchronization mechanism.

27. What do the numbers (20W40, 50, etc.) that show on the oil packages mean?

These numbers that are shown on the automotive oil packages (30, 40, 20W/40, etc.) correspond to the SAE (Society of Automotive Engineers) classification. The classification is based on the oil's viscosity at 100 °C. It has two grades, one for low temperatures (from 0W to 25W) and the other for high temperatures (from 20 to 60). The letter "W" means winter and it represents the first number. The greater the number, the greater will be the viscosity and the oil can support higher temperatures. Lower levels support low temperatures without solidifying or jeopardizing pumpability.

Single-grade oils can only be classified in one grade. Multi-grade oils fall under both temperature ranges because they have less viscosity variation in different temperatures. In this way, SAE 20W/40 multi-grade oil acts in low temperatures like a 20W oil and reduces wear when starting a cold engine, and in high temperatures acts like a SAE 40 oil, having a wide usage range.

Another very important specification is the API (American Petroleum Institute) category.