Making the switch from conventional to synthetic oil

Discussion in 'SN95 4.6L Mustang Tech' started by stangGT97, Aug 18, 2006.


  1. stangGT97

    stangGT97 New Member

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    Hey everyone,

    It's almost time for my next oil change, and I really want to try out synthetic oil in my car. I have about 87K and have been using a synthetic blend for the past 20,000 with no problems. Will switching to a full synthetic oil cause any problems with my car? I was searching but I cannot seem to find a definitive answer! I believe my motor has been rebuilt at some point (it has Jan 2000 stamps on the block, found out when changing clutch), so I don't know the actual mileage of the motor. Go figure, it has a clean Carfax report too :notnice:

    So what do you recommend? I was thinking Mobil 1 5W-30 with a Motorcraft filter... but do you think I should stay away from synthetic? Also, I've heard you may need to do an engine flush prior to running a full synthetic oil, is that true?

    Thanks! :)
    #1
  2. Kilgore Trout

    Kilgore Trout Fried or Broiled ?

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    Full synthetic oil is too expensive.
    #2
  3. mustangkid05

    mustangkid05 New Member

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    stay where ur at
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  4. Mustang5L5

    Mustang5L5 Car used in adult film "Highway Gangbang-InDaButt" SN Certified Technician Founding Member

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    I honestly think the only thing synthetic oil really does is lighten your wallet.
    #4
  5. stangGT97

    stangGT97 New Member

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    Well, that may be so... but that doesn't really answer my question. I was hoping that someone could comment (maybe from experience) regarding switching to synthetic, whether they had any leakage problems afterwards and whatnot. I know it is damn expensive though, thank God for Walmart. :nice:
    #5
  6. Kilgore Trout

    Kilgore Trout Fried or Broiled ?

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    No one answered your question because they are all to polite to tell you to do a f'n search for this extremely common question. All of them but me anyways :D
    #6
  7. stangGT97

    stangGT97 New Member

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    :shrug: I did search and went through like 5 pages of threads but didn't get any answers, if I did, I wouldn't have posted this thread. At least it's not a gear, exhaust or wheel thread... then I would say you have something to rag on me for :nice:
    #7
  8. stng

    stng New Member

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    I have never heard that you need to do a flush when switching over to synthetic... Every Mustang I have ever owned has been used when I bought it, and the first thing I have always done is switch over to sythetics. Dont really know if it helps that much, I have never had an engine failure though. I have always used mobil 1 synthetic and I used to only use motorcraft filters but in the last year I switched over to K&N oil filters. They have an antidrain back valve in the filter and since I made the switch I virtually have Zero start up noise in the morning now. The only thing I have heard is that once you switch to synthetic you are not supposed to switch back to conventional oil, dont know how true that is though...
    #8
  9. Kilgore Trout

    Kilgore Trout Fried or Broiled ?

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  10. stangGT97

    stangGT97 New Member

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    :crazy:

    Thanks for sharing your experience. I thought the Motorcraft filter has an antidrainback valve as well? What about the Mobil 1 filter? Pretty pricey but I think still cheaper than the K&N
    #10
  11. BurningRubber

    BurningRubber Active Member

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    I switched from dino oil to Motorcraft at 93k on it. Its semi-synthetic, but I wouldnt be scared to switch to full synthetic. I have heard great things about the Motorcraft oil though.

    Most of the hype about switching to synthetics with mileage is that it cleans so well, that it may remove some of the sludge or buildup holding certain seals together, thus causing a leak.

    But basically the steps to switch over to synthetic are this (from my knowlege)... drain old oil, remove old filter... screw on new filter, fill up with synthetic. Thats how I would do it.
    #11
  12. 46gtsblown

    46gtsblown Founding Member

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    Just switch.
    DO NOT CHANGE AT 3K change at the reccomended interval in your hand book or dio like I do and change the oil 1time a year with a filter change at 6 months.
    I have been doing this for the past 11 years and the motor is spotless inside.
    In europe the standard is 10k between changes not 3k.
    The hype being pushed by the oil companies is total BS don't believe the hype.
    I know I do not hold a popular opinion on oil changes but that doesn't mean I am wrong.
    Use quality oil and change it 1 time per year with a filter change at 6 months.

    Dwayne

    Dwayne
    #12
  13. Mustang5L5

    Mustang5L5 Car used in adult film "Highway Gangbang-InDaButt" SN Certified Technician Founding Member

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    There is a place that you can send an oil sample too that will tell you exactly how often you should change your oil. They do it by metal content and contaminants in the oil.

    I don't have a link to the testing site however
    #13
  14. miller766

    miller766 New Member

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    Ok I have heard that BS about not using full synthetic on a low mileage car cause it's supposively bad. Then why do corvettes and other high performing cars come with it straight from the dealer? A full synthetic oil is ALWAYS a good choice as long as you go with a decent brand and not some cheap crap. I have always used Mobil one or Royal Purple. They can be pretty pricey but it's a good investment to protect what is like the heart or your car. They have used both of those oils in race cars so they definately hold up better than conventional oils. Also, I used to run a motorcraft filter but recently I switched over to the K and N as well. Its a K and N so I figured the quality is probably better. Cost me 26 dollars for the oil and filter at Advanced Auto Parts. I say.....go full sythetic. You won't regret it.
    #14
  15. black_96_GT

    black_96_GT New Member

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    I have heard of doing a flush but I think that is someone trying to make some money (Jiffy lube).
    #15
  16. bdcardinal

    bdcardinal tree hugger

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    the testing place is called Blackstone Lab. if you go to bobistheoilguy.com there is a lot of talk there about the lab results.

    you can switch to synthetic no problem, and switch back and forth from conventional at any time. the thoughts of only being able to do one or another are old school and are only carried on by people who dont know any better. i switched my stang to Mobil 1 at about 95k miles and experienced no problems whatsoever. a flush is completely unnecessary.

    like as said above, you can push out the changes to 5 or 10k miles no problem. Porsche now recommends 20k OCIs (oil change intervals) for Cayenne Turbos. they do have a 9 quart capacity though. i would suggest changing out the filter halfway through and topping off the oil. for oil, Amsoil, Mobil 1, Redline are all good choices for a street car. Royal Purple is a bad choice for a street car, since the additive package is not friendly for street driven cars.

    the best deal ive found for Mobil 1 is at Costco. its about $26 for a 6 pack. i get my M1 there and then have a stash of about 30 FL-820S filters at my house.
    #16
  17. Todd00GT1

    Todd00GT1 New Member

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    You should be able to switch over to synthetic oil w/no issues. I use Amsoil 5w30 and do an oil/filter change every 6 months. I also use an Amsoil filter.
    #17
  18. stangGT97

    stangGT97 New Member

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    Cool, thanks for the info... do you use the Mobil 1 extended performance, or just the regular synthetic? Regular synthetic 5w30 is about 22bux for a 5quart jug, then I'll have to get 1 more quart, but the extended performance is about 27-28 for the jug. I think the extended is rated to 15k miles
    #18
  19. bdcardinal

    bdcardinal tree hugger

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    i just use the regular M1.
    #19
  20. stangGT97

    stangGT97 New Member

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    :nice: excellent. I will try out synthetic on this oil change
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