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extremeiceman04
Lv 4
extremeiceman04 asked in Cars & TransportationMaintenance & Repairs · 1 decade ago

Pop Quiz: What does "W" stand for in 10W-30?

If you get this wrong you should never again answer a question in automotive repair. 10 points to first correct answer.

Update:

Paul congrats on being the first. Your recognition will be awarded when it is possible to do so (in about 4 hours)

Update 2:

Ok, for all of you that said weight... you fail. STOP ANSWERING QUESTIONS IN AUTOMOTIVE REPAIR!!! You do not have even basic knowledge of automotive repair. For all of you who said winter, you are correct and already knew that you were correct.

Update 3:

Jeremy, you especially fail. While velocity is what is measured through the test equipment, viscosity is the numerical rating applied to the oil.

7 Answers

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  • Anonymous
    1 decade ago
    Favourite answer

    Weight is what people usually think of, but it's "winter."

    Those oils are rated for winter use.

  • Shane A
    Lv 7
    1 decade ago

    The W in 10w-30 stands for Winter. In cold temperatures the oil can be "pumped" as easily as a comparable 10 weight oil and the 30 is the viscosity. Thank you for the 10 points.

    Source(s): ASE mechanic since the days of NIASE (1982)
  • Anonymous
    1 decade ago

    Winter.

    The SAE classifications characterises the viscosity at low and high temperature of the lubricant. The grade is given by two numbers separated by the letter W (meaning winter).

    The first number, followed by W represents the low temperature viscosity, 5W, 10W, 15W... the lower this number, the more fluid at low temperature the oils, the easier the engine starts.

    The second number gives the high temperature viscosity: 30, 40, 50. The higher this number, the more viscous the oil when hot.

  • Firebird
    Lv 7
    1 decade ago

    Winter.

  • Bigg Dogg
    Lv 4
    1 decade ago

    Weight..or possibly winter, but the better quiz would be to ask what does the 10 and the 30 represent.....

    What do you think??

    ever heard of viscosity??

  • poecilotheria metallica keeper
    Lv 7
    1 decade ago

    winter

    Source(s): auto body tech
  • Jeremy H
    1 decade ago

    W is the weight of the oil....examples are 5w, 10w, 30w.....the second number is the velocity.....the higher the numer the thicker it is.....

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