Conventional VS. Synthetic
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Tuned
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Conventional VS. Synthetic
i have a 99 250 5.4 that i bought from my uncle, and it has 165k miles on it. he used 10-30 quaker state since he got it almost new. my question is can you switch from conventional to synthetic oil after that long? what would be the pros and cons, if any.
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A possible con is that some seep/weep may occur at various seals. Synthetics are known for that. However, if that happens you can simply go back to conventional if you aren't happy.
Not that it's guaranteed, only that it MAY happen. Don't worry much about it.
You'll feel better about your decision if you Google "synthetic motor oil" and read up on it.
Not that it's guaranteed, only that it MAY happen. Don't worry much about it.
You'll feel better about your decision if you Google "synthetic motor oil" and read up on it.
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. However, if that happens you can simply go back to conventional if you aren't happy.---are ya sure bout that mr.incredible? i was always under the impression ya cannot revert back-or-shoudn't--but i am also very impressionable!
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From: Snohomish, WA
Originally Posted by Mr Incredible
A possible con is that some seep/weep may occur at various seals. Synthetics are known for that.
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You are right, Stalwart, that it was a problem 20 years ago. Seals are better now and that's why it doesn't happen very much any more. However, it can still occur due to the nature of synthetics. I, personally, don't think it is much to worry about nowdays, but, again, it can happen.
Buzzbait, somebody's been lying to you. Hypothetically, a body could change their oil every week regardless of mileage and use a different oil and suffer no ill effects. Syn-dino-syn-dino, etc. Each is compatible with the other. Back in the OOOOOOld days, before it was all figured out, some oils were not compatible with others. Such is no longer the case with what we buy from our normal markets.
Buzzbait, somebody's been lying to you. Hypothetically, a body could change their oil every week regardless of mileage and use a different oil and suffer no ill effects. Syn-dino-syn-dino, etc. Each is compatible with the other. Back in the OOOOOOld days, before it was all figured out, some oils were not compatible with others. Such is no longer the case with what we buy from our normal markets.
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Here's a simple explanation I found on sythetic and seal leakage:
"Synthetic oil causing oil leaks is another commonly spread myth. The truth of the matter is that if all your engine seals and gaskets are in good condition, synthetic oil will NOT leak in your engine. The myth started because on occasion, an engine will leak with synthetic oil, but not dino oil. The reason for this is that the smaller molecules of the synthetic are able to get past very small crevices, where the larger molecules of dino oil cannot. But this does not mean that the synthetic oil has caused the leak, it simply has "discovered" an infant leak, and regardless of what oil you are running, this infant leak will eventually grow to a size that will allow dino oil to occupy and pass also. Synthetic oil has not been shown to deteriorate engine seals or gaskets. It is not some evil solvent that will break down sealant, or anything like that. Like was said earlier, it is just a man-made base stock, that is uniform and smaller in molecule size than dino oil. Nothing more, nothing less."
Again, it's not a big deal, it just sometimes weeps/seeps a little.
"Synthetic oil causing oil leaks is another commonly spread myth. The truth of the matter is that if all your engine seals and gaskets are in good condition, synthetic oil will NOT leak in your engine. The myth started because on occasion, an engine will leak with synthetic oil, but not dino oil. The reason for this is that the smaller molecules of the synthetic are able to get past very small crevices, where the larger molecules of dino oil cannot. But this does not mean that the synthetic oil has caused the leak, it simply has "discovered" an infant leak, and regardless of what oil you are running, this infant leak will eventually grow to a size that will allow dino oil to occupy and pass also. Synthetic oil has not been shown to deteriorate engine seals or gaskets. It is not some evil solvent that will break down sealant, or anything like that. Like was said earlier, it is just a man-made base stock, that is uniform and smaller in molecule size than dino oil. Nothing more, nothing less."
Again, it's not a big deal, it just sometimes weeps/seeps a little.
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From: Stephensville WI
My wife insists on synthetic in her Crown Victoria. Asides from costing more but extending drain intervals I see no benefit to using it. Fuel mileage did not go up, the engine isn't quieter.
I'll stick with dyno oil for the truck and change it every 3000 miles.
I'll stick with dyno oil for the truck and change it every 3000 miles.
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From: Plainfield, IL
My dad bought the 1992 f-250 in my sig and ran MOBIL 1 syn oil in it from 60,000 miles (which is when he bought it). We firmly believe that is why it has lasted so long and runs so well. My cousin had a 86' burban with a 350 that he ran syn in since new and he had over 325,000 when his teenage son decided to start doin nutral drops from 5000 rpm and blew it up (a Ford would of handled it,but you know). I run syn oil in everything I own now from years of personal proof. just my .02
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I also agree that using synthetic is better, it may cost a bit more but you can run it longer and what is the cost of a new motor. I decided to use it here since finding a new V-10 would be next to impossibile.
You may also consider using the 5W-30 since that is what Ford is recommending.
You may also consider using the 5W-30 since that is what Ford is recommending.
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From: New York
I just switched over to Mobil One synthetic on my last change. It costs more, but since changing the oil and filter on a SD is such a pleasure, it saves any cost of having someone else doing it. Hopefully it'll help the motor run better for longer. Same oil I use in my Mustang and the manual calls for a synthetic blend.
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From: Dryden ON.
I use the syntech oils - I live in avery cold climate and the vehicles start way better with the synthetics in them. I wil usualy breake the vehicle in with the regular oil then I switch to the synthetic.