First, the packaging knowledge is great!

Strict implementation of standard lubricating oil, bottle cap, bottle body and bottle bottom have manufacturer's trademarks; You can buy with confidence.

1. There is no manufacturer's trademark on the bottle cap, but it is on the bottle body. It was packed by the dealer himself. This kind of oil has API virtual standard, SG level dares to mark SM level. Most 4S stores have this oil. This kind of oil, generally there will be no fake oil. It's just that consumers spend SM-level money, but buy SG-level money.

For example, most of the special engine oils for 4S are marked with SM grade, and SM is all high-grade vehicles with a grade of over 600,000 in synthetic engine oil. A Wuling Hong Guang, you also use SM class. No kidding!

You can buy a three-standard bucket and try it. First of all, you will find that the engine is loud, which is caused by the thinnest oil film of the true SM class. Then you will feel that you have a fast start, a light throttle and low fuel consumption. When changing the oil, you will find that the oil is black and even the third filter is blocked. Due to the poor quality of the original engine oil, a large number of deposits will be produced on the relevant surface of the engine block. After switching to high-grade engine oil with good cleanliness, these deposits will loosen and fall off and fall into the engine oil.

There are no trademarks on the bottle cap, bottle body and bottle bottom. What's more, the bottom of the bottle has the manufacturer's trademark for producing plastic barrels. Please buy this lubricating oil carefully. 4S also has this oil, so be careful to identify it.

Second, before and after the logo text trap!

1, understand the true meaning of SAE and API.

Sex 15W-40 is an oil suitable for all seasons. (- 15℃-45℃)

Sex 20W-40 is summer oil.

Sex 10W-40 sex 5W-40 is winter oil.

Lubricating oil using imported base oil can be SEX 15W-40, and lubricating oil using domestic base oil can be divided into summer oil and winter oil.

A driver said: Summer sex 15W-40 feels thin. This is a misunderstanding. The better the base oil, the closer to colorless water.

API letter S starts with gasoline engine oil, and letter C starts with diesel oil. Good lubricating oil is now used for gasoline and diesel.

CNG is gaseous natural gas, LNG is liquid natural gas, and there are dual-fuel natural gas (oil to gas). These three are not API standards, but industry standards. These lubricants should not be mixed and used indiscriminately. Light causes the exhaust gas to fail to meet the standard, and heavy causes the engine life to be reduced. There is a simple reason. Different fuels, different molecular structures, and different impurities produced by combustion.

2, fully synthetic and in line with fully synthetic and semi-synthetic word games!

Engine oil has only synthesis and total synthesis, which accords with the fact that total synthesis and semi-synthesis are word games. How to distinguish? It's simple. Oil change mileage. In China, it is 65,438+0,005, and the total synthesis is 20,000 (no more than half a year). 4S requires 5000 kilometers, hehe, which means there are few additives. Good oil is expensive, but at least 1000 yuan, and the cheap 5000 yuan. Don't say that you use good oil to save fuel, and everyone will calculate the cost performance of 1:3. This is also the main reason why 4S and oil change shops have no good oil, long oil change mileage and low profit.

3. Useful manufacturer certification.

Lubricating oils of big brands are the matching oils of automobile manufacturers. Manufacturers are very strict about the choice of matching oil. The lubricants of big brands are all marked with the quality certification of a certain manufacturer.

What are the so-called well-known brands at home and abroad on the market now, and how many are on the signboard?

As long as you play these, it is a real big brand. There is no charge for passing the factory certification, just look at the quality. The API is ok. . . . You know)

4. Please note that the following signs are used for vehicle types:

Pay attention to the tail logo used in the model and choose the oil that suits you. But there are also funny, SM-grade oils, and BYD's full range is recommended. You should be careful with this.

Third, and finally, the price.

You get what you pay. At present, there are more than 8 pieces of base oil in China, and the cost of adding hydrogen once is 3 pieces. Three kinds of hydrogen should be added three times, which is about 17 pieces/liter. The third kind of import is about 14 block/liter (the high quality of crude oil leads to less hydrogenation times). In other words, the retail price of 4 liters SG/CD is not less than 100 yuan, and the wholesale price is not lower than that of 80 yuan.