my car is going to have an oil change in a few days and i need help buying new motor oil.
my car has 171,000 miles and my dad told me to get 10w-40 or something, but what do the numbers stand for?
and is this the correct one to get for my car?
2006-08-14 15:00:14 · 13 answers · asked by b3nsonx 2 in Cars & Transportation ➔ Maintenance & Repairs
your dad told you right..
10 stands for how thin the oil can get if the weather gets cold.
That is good because oil can get so thick the engine won't turn over fast enough to start.
40 represents how thick the oil can get when it is hot.
There are things called polymers in the oil that make it chemically thicker or thinner according to the temperature.
Years ago oil only had one number. They hadn't invented the polymers yet so they had to rate oil by its thickness so people knew what to expect.
If you lived in Minnesota where winters are very cold you had to buy #10 oil for winter or #5 if they had it.
In the summer you had to switch to #40 to protect the engine because the heat would thin the oil.
#40 oil is pretty thick even in the summertime.
Hope that helps
2006-08-14 15:23:33 · answer #1 · answered by Harley Charley 5 · 1⤊ 1⤋
Motor Oil Bottles
2016-10-13 22:43:25 · answer #2 · answered by placzek 4 · 0⤊ 0⤋
the numbers used to describe engine oils are two parts code: Viscosity and Winter Viscosity.
Viscosity is the oil’s resistance to flow. The thicker (higher viscosity) of an oil, the slower it will flow. In most occasions, you will see oil viscosity measurement in lube articles stated in SAE viscosity.
The letter W on the other hand means that oil viscosity has been tested at colder temperature. If they are not shown that means that the engine oil was tested at 100° C which is considered the approximate engine operating temperature. Simply put, a SAE 30 engine oil is the same viscosity as 10W-40 or 5W-30 at 100° C. The difference is that the engine oil performs like SAE 10 or SAE 5 would perform at cold temperature specified but still has SAE 30 viscosity at 100° C.
I think this article will help you understand it all http://www.fueleconomysolutions.com.au/what-do-the-numbers-on-engine-oil-mean/
2013-11-29 01:21:29 · answer #3 · answered by Anonymous · 0⤊ 0⤋
10W 40 multi-grade oil is a good choice for your sorta worn engine, but say a 5W 50 is not as good a choice for you due to the wider range.
So, get what your Dad says.
Example, a 10W-40 designates a common multi-grade oil. The first number associated with the W is not rated at any single temperature. The "10W" means that this oil can be pumped by your engine as cold as a single-grade 10 weight oil can be pumped. "5W" can be pumped at a lower temperature than "10W". "0W" can be pumped at a lower temperature than "5W", and thins less at temperatures above 99°C (210°F). The second number, 40, means that the viscosity of this multi-grade oil at 100°C (212°F) operating temperature corresponds to the viscosity of a single-grade 40 oil at same temperature. The governing SAE standard is called SAE J300. The motor oil grade and viscosity to be used in a given vehicle is specified by the manufacturer of the vehicle.
2006-08-14 15:23:40 · answer #4 · answered by randyrich 5 · 2⤊ 1⤋
They stand for viscosity and the correct oil for your car is what the manufacture says. Do you drive in mostly hot or cold temps? In cold weather the thicker the oil the harder to start your car. Thicker oil will not leak out of faulty seals as quickly as thin oil. Thinner oil will also yield higher MPG!!
2006-08-14 15:15:48 · answer #5 · answered by Silvertooth 2 · 1⤊ 1⤋
If you are not having oil pressure problems..... there is no need for 10w-40..... which would more then likely shear to a 10w-30 in a short while anyway.... (due to having alot of volume index improvers)... 171,000 miles is nothing...... You'll be fine with 5w-30 or 10w-30......
2006-08-16 01:51:20 · answer #6 · answered by 572ci. 5 · 0⤊ 0⤋
Go with Castrol 10w-30 all year long and you can't go wrong. Go to link for further info. In a nutshell: 20W-50 is a 20 weight oil that will not thin more than a 50 weight would when hot.
2006-08-14 15:08:29 · answer #7 · answered by Anonymous · 0⤊ 3⤋
Well, it would help to know which car you have. Then the 10W40, is its viscosity rating, cold, and hot. 10 is for the start up, and the 40 is for when it is warmed up. The W has some meaning, of cold weather quality in the oil to help it be fluid, more for up north weather.
2006-08-14 15:05:00 · answer #8 · answered by Silverstang 7 · 2⤊ 3⤋
Use 10 W 30. This is the best for most cars. Unless you are driving a diesel, then you'll want 15 W 40.
2006-08-14 15:06:46 · answer #9 · answered by vegigirl 2 · 0⤊ 3⤋
the first number stands for the weight it has when the engine is cold,the second letter stands for winter and the last number stands for the weight it has when the car is warmed up.
2006-08-14 17:45:02 · answer #10 · answered by Anonymous · 0⤊ 1⤋