Good Info about Oil.

Discussion in 'Mechanic and Repair' started by Precision, Nov 28, 2006.

  1. Mark in MD

    Mark in MD LawnSite Senior Member
    Messages: 322

    This is the way I understand it:

    10W-30 oil in your mower, is exactly the same as SAE 30 oil in your mower, when at operating temperature. The difference is, the 10W-30 oil will behave exactly like a SAE 10 weight oil when cold, which means it is thinner than SAE-30 oil when cold. But this is not a good thing, if the manual calls for SAE 30.

    Don't confuse the W in 10W-30 as "weight." I believe the W stands for "winter." Nevertheless, when the engine reaches operating temp, even in winter, the 10W-30 is just like SAE 30.

    On occasion, I've run out of SAE 30 and I've used 10W-30 in its place. I've found that 10W-30 in my Kaw will be consumed much faster than SAE 30, which is what he manual calls for in my Kaw engines. I guess it's too thin during warm up, and therefore burns off. Therefore, I really try to stick with SAE 30.

    Yes, it seems harder and harder to find nowadays.
  2. meador56

    meador56 LawnSite Member
    Messages: 90

    W is for weight. Iused to be in sales for big oil jobber. Most old wives tales are told for the oil companys sake, you guys have heard them like you shoud not change brandsin used equipment, bull. I use full pao's in trucks after they are broken in. In my diesels which range in hp from 33 to 425 we use 15-40. I used stick with 1 brand but for conveniece have gone back to Rotella. Most people think theres a dollars worth of difference between best and worst actually more like a nickels if even. Mostly stick with name brands but have been using Wal-Marts super tech 10-30 full syn in trucks made by major and at 13.84 for 5qts is great buy. I also switched all my hondas over and with good results. Oil changes are more important than oil brand.
    IPADDL likes this.
  3. Mark in MD

    Mark in MD LawnSite Senior Member
    Messages: 322

  4. meador56

    meador56 LawnSite Member
    Messages: 90

    Looks as if most don't know that W stands for winter and not weight. The manufacturer rep that helped to train me called it weight. In effect 10W30 pours like 10 and protects like 30. I have used this principle for years and we haven't had any oil failure
  5. jestal

    jestal LawnSite Member
    Messages: 7

    The reason that straight 30 was specified in some engines was to avoid the viscosity improvers that are required to make a 10W30 oil. Viscosity improvers are long chain polymers that react to temperature and allow the viscosity swing of a 10W30 oil. The viscosity improvers "thicken" the base 10 weight oil to make it like a 30 when hot. Magic. Viscosity improvers can also cause problems with deposit formation in the piston ring belt area causing ring sticking. So....some heavy duty engines specify non-viscosity improver the straight weight 30.

    Ever notice that multi-vis oils were pretty much taboo for heavy duty diesel engines until the early-mid 90's?? That is because of the viscosity improvers. VI packages of the late 70's and thru the early/mid 80's were notoriously bad for ring belt deposits. Due to the high concentration of VI in the 10W40 oils those were especially bad.

    Today this is all pretty much ancient history. The viscosity improvers in today's oils are all synthetic and there is little to no risk of ring belt deposits and ring sticking with multi-vis oils. Also notice the proliferation of 15W40 diesel oils that meet all diesel specs. The VI packages are excellent. No real need to avoid them these days.
  6. jestal

    jestal LawnSite Member
    Messages: 7

    "W" in 10W30 oil definitely stands for Winter. People have used W to stand for weight in casual conversation but in the API oil classifications the W is clearly for "winter" to delineate the "cold" oil viscosity as it would be in the winter.
  7. DawgGrad00

    DawgGrad00 LawnSite Member
    Messages: 50

    What would be the correct hydro oil to use in my 2000 Grasshopper ZTR? Grasshopper says to use there hydro oil only and when I bought a quart of it, I noticed that there was not weight listed on the container. I also felt as if I bought liquid gold when they told me how much it was per quart. I'm sure there is an alternative but have had no luck in finding it. Any info would be greatly appreciated.
  8. rpauls

    rpauls LawnSite Member
    from NW NJ
    Messages: 11

    Have you tried the 15-50 mobile1 yet? What did you think? I am considering the same for my kohler which also calls for straight 30. Why is there no synthetic 30W?

  9. Mark in MD

    Mark in MD LawnSite Senior Member
    Messages: 322

    I'm not sure, but I think it would a contradiction of terms. 30W I believe is by definition a straight oil with a viscosity of 30. My guess is they have not figured out how to make a synthetic that behaves EXACTLY like straight oil. I mean, if they did, from that maybe we could then make man-made gasoline, and to hell with the middle east.
  10. Bill Kapaun

    Bill Kapaun LawnSite Senior Member
    Messages: 964

    Amsoil ASE 10W-30/SAE 30 for one

    A synthetic multi weight oil is similar to a straight weight oil by its nature.
    Think of water. Pretty much the same viscosity from 33 to 211F.

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