changing to syn motor oil

[sothpaw]

... I keep forgetting to relay this:

My metallurgy prof. and I were talking about syn oil and he said there was an old ASME article years ago that suggested that you get the full benefit of changing a car to syn. by just adding some. Maybe it was 20%? I personally wouldn't risk it in the daily driver unless I found the orig. article.

 

[blackvette89]

iyou may get away with it in a 93, i tried it in an 89 i was leaking a little. i changed back without the leaks!!

 

[FordNoMore!]

That is because They did not start using Mobile 1 until the LT-1 motor came available,92, After that, it became a Corvette standard, Syn Oil in a Motor not gasketed for Synthetic oil, will cause leakage, as proven with Pre LT-1 engines.

 

[Bad89coupe]

My 89 coupe has been usin synthetic for quite some time now before I even owned it. I have't had any leakage problems with using the mobil 1

 

[Edmond]

My 89 coupe has been usin synthetic for quite some time now before I even owned it. I have't had any leakage problems with using the mobil 1

Same here, no leaks.

 

[Vettelt193]

Back on the original subject of the synthetic and regular oil blended together.... Yes, I have read a few articles that talk about the benefits of the blend. By mixing the two oils you retain most of the synthetic's qualities, while getting a much lower price. This is why the oil companies started making the synthetic blends too.

 

[89conv-vette]

Mobil 1 syn

I HAVE USED MOBIL 1 SYN OIL IN MY 89 CORVETTE SINCE THE FIRST OIL CHANGE, AND NO LEAKS. I HAVE USED MOBIL 10w-30w IN ALL MY CARS, GM OF COURSE, SINCE ABOUT 1986 AND NO OIL LEAKS. AND I DO GET ABOUT 1 1/2-2 MPG MORE WITH MOBIL 1.

 

[jmccloud]

Mobil

My '95 came with Mobil 1 and all changes stayed with it.
My '88 Blazer started consuming oil at about 120,000 miles (1 quart in 1500miles) and quit when switched to Mobil 1. It now has 180,000 and goes 3,000 between changes with no need to add.
My '41 F....rd (please excuse, it's only a tractor). benefits from it as well. When the temp is in the high 90's, I no longer have to let it cool to bring the oil pressure up when running the 6' mower. All the locals won't even put detergent oil in one of those old beasts.

 

[zog]

I bought an 86 coupe with 97,000 and changed the oil to Mobil ! 10w30...don't know what was in it before...

SO far, not a leak anywhere...

 

[bradvette]

I have never heard of a leak issue by using full synthetic on a pre-LT-1 engine. What is this "proof" you are referring to?

 

[oldace84]

Dosen't it make problems if you have to much milage on your vette.....Like if you used it from the begining of your vettes life....then no problem....
Mine has 87k.......so I have to stick with the "other oil"
Am I right???????
tony

 

[Vettelt193]

Dosen't it make problems if you have to much milage on your vette.....Like if you used it from the begining of your vettes life....then no problem....
Mine has 87k.......so I have to stick with the "other oil"
Am I right???????
tony

no, it will not cause a problem... that was a myth started many years ago.

HOWEVER:

It may cause leaks. One of the reason why LT1 and LT4 engines have leaks is the synthetic oil. To make a long story short, the benefit of the synthetic is the consistancy of the oil... basically, all of the particles are the same size. this is also the feature that causes a higher probability of leaks. In conventional oil, if there is a small opening, a larger particle can come along and 'plug the leak'... with synthetic, all the particles are the same size... if there is an opening big enough for one particle of oil, all the rest can follow, so a leak forms.

 

[zog]

My 2 cents regarding leaks

I was told by a guy that works for Phillips 66 that changing from regular oil to synthetic in high mileage cars DOES NOT CREATE leaks....

However, over time the regular oil leaves sludge and gunk in the engine and around the seals, causing the seals to harden and get brittle. The gunk actually acts as a sealer and prevents the seals from leaking until the seals get so brittle that they break...causing a leak.

When there is a change to a synthetic oil, usually cleans away the gunk, so that the brittle seals are prone to seepage and leaks.

Makes since to me....I have changed cars from regular oil to synthetic a few times, and some leaked and some did not...it usually depends on how well the engine was taken care of prior to the change.

 

[ltcdad]

I'm in the military specializing in liquid logistics, specifically Petroleum, Oil and Lubricants. Our lab technician told me there should be no repercussions from switching to synthetic oils. The previously mentioned sludge buildup, however, is an accurate observation according to them.

One of the big benefits of the full synthetics is its resistance to viscosity break-down at high temperatures. I'm again told by our lab folks that the blends don't maintain this benefit and the viscosity begins to break down at the higher temps just like the natural oil. I prefer the full synthetic to take advantage of the consistant viscosity.

 

[warren s]

SYn Oil does not cause leaks....BUT

If you have an older car and you are running 20w 50 weight dino oil to slow down some leaks and get higher pressure, switching to 10w 30 oil of any type, SYN or DINO may leak due to the lighter weight of the product, not its molecular make up.

Mixing to save money is up to. You get less benifit than full SYN.
As the old syaing goes, you get what you pay for.

 

[kevoinc]

I switched 2 mobil 1 in my 89 last oil change,first time with syn.Car has 42,000 miles and no leaks,just my 2 centavos.

 

[Edmond]

Our local Wal Mart doesn't carry the 5 quart synthetic oil. So I'm forced to buy the 1 quart bottles for $4.25. Sucks doesn't it? :L