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20W50 motor oil

I have an old 91 corolla that burns oil. A friend suggested I switch to 20W50 oil. Will this help in terms of oil burn, engine wear, or gas mileage? How is this oil different from whatever Jiffy Lube usually gives me.


  • edited October 2007
    Did JiffyLube indicate what viscosity of oil they used for your last oil change?
  • edited October 2007
    i believe it is 10w30. at least that is what i use, when i have to add oil between changes.
  • edited October 2007

    This may help a bit with the oil burning. It's certainly worth a try. For a '91, go with anything that will keep the beast alive another year. You need worry no longer about engine wear. Gas mileage should theoretically go down, but probably not enough to even measure.
  • edited October 2007
    Is the oil burning a problem? I know it's not environmentally friendly. Is that your reason? The 20W50 motor is worse for engine wear. The valve stem seals are probably leaking oil into the cylinders and being burned. You could replace the valve stem seals.
  • edited October 2007
    "How is this oil different from whatever Jiffy Lube usually gives me."

    It is considerably thicker.
  • edited October 2007
    If you want thicker oil and the temperature only dips below 30 degrees F for a few hours a night in the winter, you should consider thicker oil. 20W50 isn't it. You can use it, but use only three quarts and use straight 30 weight for the other two quarts and you might get less oil consumption. You will notice the difference with 30 weight right away. It won't pour out like water as does the 10W30. It isn't treated to just act thicker under certain conditions; it is thicker. See if Jiffy lube has straight 30. They would probably want to sell you some additive at a good markup. Find some other place that will give you the oil you want if Jiffy Lube won't.
  • edited October 2007
    On the freak chance it could be something simple, you might check the PCV valve and make sure it's not plugged up. This could promote oil burning.

    Heavier oil such as 20/50 could help but if you live in a northern climate or the mountains where the temp drops into the freezing range or lower on a regular basis you should not use it.
    20/50 oil on a 20 degree day has the consistency of tar.
  • edited October 2007
    Yea using heavier oil is a good idea. You might want to follow pleasdodgvan's suggestion, it has some merit.

    However like pleasedodgevan I have the suggestion that you loose the quick lube places like the one you have been using. Keep away from the quick change places. We hear far too many horror stories about them. Some may be fine, but many pay the help little, demand fast changes and that results in a high percentage of errors. Too many live by selling you something you don't need at inflated prices.

    Find a good local mechanic and stick with them for your needs.

    Don't go to the quick lube places, even for directions.
  • edited October 2007
    To avoid the cold weather starting issues with 20w50, you could try a dyno 10w50. It's typically less desirable because of the large number of additives it needs to get the wide 10-50 spread, but for an old 91 oil burner, it may be just the ticket.
  • edited October 2007
    you could try a dyno 10w50.

    Who makes a 10w50?? Never seen it. I've seen 5w50 - synthetic by Castrol...but NEVER seen anything near that range as a dyno oil.
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