GOING FROM SYNTHETIC TO CONVENTIOAL (?)

[SFCP]

I was interested to hear from anyone who has used strictly synthetic oil in their engines and what they do after 100-150k when the engine developes a minor oil leak that is too costrly to repair, yet nothing that would harm the engine?
Is it at that point you go to a thick non-energy conserving conventional HM oil, or just regular conventional? I have heard that just because you use synthetic, engine seals will still deteriorate with age. I also wondered how an engine would be effected by going from a slick, fast flowing synthetic after 10 years of use back to a conventional?

 

[TimVipond]

There are some engine stop leak additives you could try. There are now some High Mileage synthetic and nonsynthetic oils with these additives already added you might try. You could try a slightly higher viscosity (thicker) oil. You can switch from synthetic to petroleum without a problem.

Generally petroleum oils are harder on seals as they could put a coat of varnish on them and thus separating the seals from fresh oil which helps keep the seals lubricated and pliable. If varnish forms on the seals, it could lead to drying out of the seals which could lead to cracking.

The group IV and V synthetic oils rarely will varnish seals to the point where they can dry out.

Which synthetic oil were you using and which engine?

 

[SFCP]

It's not about me, I'm not using syn's. I was inquiring on what others do. So in other words, using conventional and changing it often will assist in keeping the seals pliable?

 

[TimVipond]

It will help. Synthetics will do it better, even with longer oil change intervals. The dry seal leakers I know of used conventional oils. I don't know of any that only used group IV or V synthetics.

 

[SFCP]

Do the blends offer better seal protectiong?

 

[TimVipond]

Generally speaking, blends (which only contain 10 to 30% synthetic), do most things better than conventionals, but not as well as group IV/V synthetics, especially with long oil change intervals.

 

[Steve S]

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I also wondered how an engine would be effected by going from a slick, fast flowing synthetic after 10 years of use back to a conventional?

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What? Slick, how is syn slick? Fast flowing, how does it flow fast? As compared to conventional.

 

[SFCP]

k

 

[SFCP]

Steve S.. YOu have got to be kidding, right? After all these years of BITOGS existance and all the talk and discussion about how syn flows better and is more slick..
wow.. you really were just being sarcastic, right?

 

[Steve S]

No I am not being sarcastic The wear is about the same with syn or conventional.I have seen the insides of many engines in the 23+ years as a mechanic..opps !!! Technician . The oils are better refined etc than the olden days but a hint if the syn base stocks are slick why do they have the same additive amounts as conventional oils? Why does limited slip additives have to added to some syn rear end oils ? I don't know about the free flowing though,it is in extreme cold ? if so that is one of the advantages of syn oil ,and there are more but I don't sell syn oil so I don't hype them .I have used syn oils and can say if an engine really needs syn oil the manufacture will recommend them.

 

[SFCP]

Steve, point taken

I can apreciate where you are coming from with all your experience. It is an interesting point tht you make with regard to the additive levels in the synthetics.

 

[TimVipond]

Actually group IV/V synthetics have fewer additives than conventional oils. A conventional may only have 75% base oils, the remainder additives. Group IV/V could be as high as 90% base, with 10% additives. Synthetic base oils are more chemically stable than conventional base oils with better low and high temperature performance, thus less antioxidants, viscosity improvers, pour point depressants, acid neutralizers, etc. are needed.

 

[Merkava_4]

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Do the blends offer better seal protectiong?

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MaxLife blend does! But it's not energy saving, so therefore you're not allowed to use it.

 

[Steve S]

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Actually group IV/V synthetics have fewer additives than conventional oils. A conventional may only have 75% base oils, the remainder additives. Group IV/V could be as high as 90% base, with 10% additives. Synthetic base oils are more chemically stable than conventional base oils with better low and high temperature performance, thus less antioxidants, viscosity improvers, pour point depressants, acid neutralizers, etc. are needed.

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Antiwear additives .

 

[spOILEDrotten]

I can personally testify, that when buying a vehicle new, I have never EVER had one single leak from any car when synthetic lubes were used from the start. This even goes for leak prone cars like Subaru and Jeep.

This is coming from a guy that drives 75K-100K a year.

The majority of leaky cars I've owned were utilizing dino oil.

 

[Merkava_4]

The best of both worlds would be Maxlife full synthetic, but the OP will not allow himself to use it because it is not energy conserving.

 

[ARB1977]

I would try some auto rx to see if that helps with the leak? If it works use maintence doses with what ever oil you want.

 

[yota4me]

I'd also highly recommend Auto-RX with conventional oil (per application instructions) to stop the oil leak & recondition the oil seals, then use preferred oil.