secret question
Thread Starter
Pro
Joined: Sep 2003
Posts: 655
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From: Rio Vista ca.
secret question
O.K., this is an oil question but I figured no one would read it if I put "oil" in the title. I tried to find an answer in "search" but I only have so much time left on the planet and there's a lot of oil stuff there.
My problem is I can't remember if my mechanic put synthetic oil in my '89 auto the last time I had the oil changed. The tag he put on the window just says 5-30 wt. oil. I need to add a quart of oil. Can I add regular non-synthetic oil even if the oil that is in the car is synthetic? Also, can I add synthetic oil to existing non-synthetic oil without causing any damage? I probably should just change the oil myself and use a decent non synthetic oil on my L98.
Any advice will be welcome.
Kim
My problem is I can't remember if my mechanic put synthetic oil in my '89 auto the last time I had the oil changed. The tag he put on the window just says 5-30 wt. oil. I need to add a quart of oil. Can I add regular non-synthetic oil even if the oil that is in the car is synthetic? Also, can I add synthetic oil to existing non-synthetic oil without causing any damage? I probably should just change the oil myself and use a decent non synthetic oil on my L98.
Any advice will be welcome.
Kim
Tech Contributor
Joined: Aug 2006
Posts: 9,933
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From: Peoria Arizona.. Resident Gold Cylon
While I have never heard of the practice of mixing oils, im reminded of the multi-million dollar business of folks trying to tout differnt oil additives, just think of all those oil additives on the shelves. So I would think no harm would come from mixing in a different quart of oil in this case synth vs non synth. I think you would be causing more damage to the motor in wear and heat from running around town one quart low. So my answer to your secret question is if I was in a pinch id do it. GC
Last edited by Goldcylon; Mar 20, 2009 at 03:13 PM.
Team Owner
Joined: Jan 2009
Posts: 73,568
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From: Somewhere in Mo
St. Jude Donor '09-'10, '14
While I have never heard of the practice of mixing oils, im reminded of the multi-million dollar business of folks trying to tout differnt oil additives, just think of all those oil additives on the shelves. So I would think no harm would come from mixing in a different quart of oil in this case synth vs non synth. I think you would be causing more damage to the motor in wear and heat from running around town one quart low. So my answer to your secret question is if I was in a pinch id do it. GC
But I would go get my oil changed ASAP. Also if you still have the receipt for your oil change it should be on it.
Race Director
Joined: May 2008
Posts: 10,742
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From: Manheim Pennsylvania
You can mix it. If you up-grade to synthetic oil you will never be able to remove all the regular oil. I have changed all my cars to Mobil 1. Never had a problem and you can feel the difference. I have seen a gain of one mile per/gal normal operation
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From: Australia
Intermediate
Joined: Sep 2008
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From: IndyNoPlace Indiana
If it was my vette I would just go ahead and change the oil,you gotta buy one quart anyway.Put in mobil-1 and a new filter then you will know what is in your engine
Go to walmart and buy it in the 5 quart jug ,it's alot cheaper than buying it by the quart at an autoparts store.
Go to walmart and buy it in the 5 quart jug ,it's alot cheaper than buying it by the quart at an autoparts store.
Thread Starter
Pro
Joined: Sep 2003
Posts: 655
Likes: 2
From: Rio Vista ca.
Thanks for all the replies, guys. I'm thinking that I'll change what ever oil is in the car to a non synthetic 5-30 wt. per the owner's manual. I've read that synthetic oils can cause small oil leaks. I'm wondering if replacing the synthetic stuff with traditional oil might slow or stop those leaks. I know that I had Mobil 1 put in the car at least once, shortly after I bought it about 3 years ago. I can't remember what was used in the ensuing oil changes.
Kim
Kim
