One of the most significant rituals of car maintenance is Engine Oil change at regular intervals. If we miss or delay this, car gurus and mechanics tell us that we are decreasing the life of our engine. If there is no engine oil in the chamber, the car engine gets seized in minutes.
People always ask us, which engine oil to use? When to change it? And what are the gradings on the box of oil? Today we will try to describe the whole phenomenon in the most straightforward manner possible so that we comprehend it once for all.
Friction and Heat
The primary function of Engine oil is to reduce the friction between moving engine parts. This not only help minimize the wear of the parts like pistons, connecting rods and crankshafts, it also helps reduce the heat.
Friction and heat are the biggest enemies of any engine.
Modern engine oil also serves the function of cleaning the sludge, residue, and detergents left over by previous oil.
Most drivers don’t know this. We link fuel efficiency with the engine capacity of the car, the quality of the petrol, fine-tuning of the engine, and the driving techniques.
I have often seen drivers at workshops complaining about the reduced fuel efficiency. The answer mechanics have for this type of issue is to clean the throttle body, service the spark plugs and even advice to replace the ignition coils. No doubt that these things play their part, but sometimes it’s just a low quality or inappropriate engine oil.
As stated earlier, engine oil reduces the production of heat. If it fails to do that, most of the energy produced by the combustion of fuel is lost in heat. Ultimately, it lowers the fuel efficiency.
Understanding the Engine Oil Gradings
Although there are many articles on the internet explaining engine oil gradings, most of the car owners in Pakistan find it a riddle. So let’s solve this puzzle.
First thing first, understand that the gradings on the engine oil box depict viscosity of the oil at specific temperatures. Note here that extreme cold and scorching hot temperatures are equally bad for the car performance and even break down the car engine. So here the engine oil plays its part and keeps the car engine in an optimum temperature range.
Traditionally the lower the grade was, the lower the temperature it can pass without damaging the engine parts. People used to have separate oils for winters (thinner) and summers (thicker). However, thanks to scientific progress, now we have a multi-grade system. This is the grading, you see on the engine oil bottles on the shelves.
Let’s take the example of SAE 10W30, one of the most used oil in Pakistan.
Some brands write it as 10W-30. Doesn’t matter, understand that there are two numbers separated by a “W”-that stands for winters. The digits which are written before W tells us the oil viscosity in cold temperatures while the ones after W portrait viscosity in hot temperatures.
Number Before W
It’s pretty simple. It is basically an exact temperature rating. 10W means; the engine oil is suitable for temperature not below than 10 degrees Celsius. Similarly, 5W means; it is ok to start the car even at 5 degrees Celsius.
Number After W
The higher the number, the thicker it gets while the engine is hot. So basically, higher the number, higher is the temperature it can withstand. For example, a 30 graded oil is thinner than a 40 one at 100 degrees Celsius.
The other symbols as API, ACEA are basically the certifications of the specifications of oil; the details regarding the added additives. Like I stated other than controlling heat, modern engine oil ensures cleaning of the engine, reducing the oxidation, and protect against deposits in the engine oil chamber.
Which Oil Grading is Best for my Car?
Let’s discuss it in subheadings to digest the answer of this frequently asked question correctly.
If you own a new car, you must have the manual with you. It is there for a purpose, always try to follow it. No one knows the engine best then the engineers who designed it. In your manual, there are written instructions regarding the engine oil. Never supersede that grading. It doesn’t matter what your mechanic tells you.
Typically the prescribed grading is done keeping in mind the engine technology, its capacity and whether the car is hybrid or conventional. Usually, new cars have engine oils gradings like 5W-40, 0W-40, and maximum 10W-30.
Many people have used cars and didn’t have the manuals with them. Understand the simple formula; the older your car gets, the more worn out its engine is. So if you have an old car but have installed a new engine, you can obviously use engine oil with less viscosity.
However, if your engine is old, never use engine oils that are thinner, you need to have enough lubrication in the engine to have less heat and less wear and tear of engine parts. Also, note that the older engines burn the engine oil and if you have thin oil in the chamber it will be eaten up more quickly. You can have engine oils with gradings like 10W-40, and 20W-50.
What about those people who are living in colder areas of Pakistan, let’s say in northern areas. The temperature there gets extremely low. The thin engine oils are best for such type of areas.
If you are living in Sindh, or Punjab and wants to travel to northern regions, remember that you can alter the number that comes before W according to the climate but never play with the second number. For example, if you use 10W-40, you can have 0W-40.
Mineral, Semi-Synthetic or Synthetic
These are the three types of oil available in the market right now. Mineral oil is the crudest one as its name suggests, semi-synthetic and synthetic have added additives in them. Mineral oil has less time interval for oil change whereas the synthetic oils can be used for a much more extended period.
Again follow your car manual and use the type of oil recommended in the booklet. Normally high-performance engines and new engines require synthetic oils as they can withstand high temperatures well. However, they are way more costly than the mineral ones.
If you are driving an old car, never think of sifting to synthetic oil as it will be useless and even cause leaks in the engine oil chamber. If you are living in colder areas, synthetic oil will enhance the life of your car’s engine as it provides maximum safety in cold starts.
When should I change Oil?
You should never delay the oil change time intervals as it causes severe damages to the engine. Follow your car’s manual; details are provided there regarding the change intervals.
Minerals oils have short time intervals from 3000 km to 5000 km whereas the synthetic oil provides time intervals starting from 8000 km up to 25000 km.
Which brand is good?
Most of the people ask which brand to go for. In the real world, it doesn’t matter as long as you are sure that the oil you are getting is genuine. You have to follow the gradings of oil, and the rest is entirely up to you. You can opt for any brand you are comfortable with.
In Pakistan, auto manufacturers ask consumers to use their engine oil brand and void the warranty if someone uses some other brand. Although it’s a bad practice, you have to follow it to save your warranty period.
My Mechanic says…
Most of the mechanics are illiterate and far from the technological advancements. So you should be very careful and never follow their bits of advice blindly. They already have created many myths in Pakistan, some of which we busted at MoreNews.
I think now that I have explained the whole phenomenon, you are good to go yourself. However, if needed get a solution from a properly trained mechanic.
The comment section is always at your disposal. Feel free to ask anything, we are here to help.