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Old 06-08-2003, 01:57 AM   #1
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Default Adding synthetic oil with conventional oil?

I've never used any modern day syntheti or synthtic blend oil in my 92 SE before (only has 55,000 original miles on it) but I've often wondered if there was anything "wrong" if someone used a quart or two of synthetic oil to an engine consisting of mostly basic conventional oil.

I guess this would create somewhat of a "synthetic blend," and would make more sense to use this type of combination - protection wise - than resorting to one of those "snake oil" engine protectants like Slick 50 or DuraLube, etc.

I changed my oil today and realized that I was short one qt. of conventional oil and didn't know whether or not I should add an extra qt. of 10W30 synthetic - since I had a few bottles left over of Mobil 1 that a friend gave me before he moved. Would this be okay?
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Old 06-08-2003, 02:17 AM   #2
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Synthetic oils were originally developed for use in gas turbine engines. In most cases they are capable of maintaining their viscosity for longer periods of use and under much greater temperatures and pressures than petroleum products. Commons synthetics used for engine lubrication today are Polyalphaolefin (like Mobil 1) or Dibasic Organic Esters (like AMSOIL). They are fully compatible with conventional oils and can be mixed, providing their ratings match.

Probably the best situation is a blend of synthetics and mineral oils, such as Golden Spectro and AGIP Sint 2000. These products seem to offer the best of both worlds in protection and extended service life. They may cost considerably more than standard petroleum products, but they also can be used for much longer periods between oil changes without losing their protective capabilities.
This is from this article. the quote is at the very bottom of the page but the whole article is quite intersting. Thanks DrJay

For a lot more info on anything you need to know you can take a look at this post by DrJay.
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Old 06-08-2003, 03:14 AM   #3
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Yes you can mix synthetic oil with conventional oil. It is a good thing although not as good as full synthetic.
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Old 06-08-2003, 03:20 PM   #4
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As long as a 3000 mile drain interval is followed, in most instances, than dino will be somewhat acceptable.

However, a Group IV oil is much more stable, keeping its viscosity longer. Its a superior product which will offer higher levels of protection and longer drain intervals (dependent on UOA to determine exact change interval) .
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