Synthetic Engine Oil

[VideoTechMan]

Im not sure if this question has been asked before, if it has pardon me...I would like to know if synthetic oil for a car would be beneficial or not. In my case I am not sure it would be a good idea to use it for my car....I have an 84 Olds Cutlass Cierra with the 2.5L engine, (4 cylinder) and the car has been very well maintained during its 19 years. My mom bought it brand new and then she given it to me, and I therefore keep up with it maintenence wise. I have always used 10W-40 oil in the car for a long time. So my question is, would changing the oil and putting synthetic blend in the car would help it any, or would it be best to just changing the oil with the regular 10-40. Ive also heard about the high mileage oil too (my car has 143K miles on it) thats supposed to help clean deposits and such, but wasnt sure if this was beneficial or not compared to synthetic. Any help would be appreciated. I will keep my car running as long as I can, since I know its very reliable for long distance road trips and still is.

VTM

[shoozleboy]

my father worked on repairing machinery for years and I remember him telling me years ago to save my money and just get the regular motor oil.

His experience was that the seals on motors and such on the machinery did not like the synthetic stuff after it had been conditioned with regular oil. Synthetic oil is pretty thin, almost like water.... it would seap through the seals that would normally hold back regular motor oil.

He was right in my case. I didn't listen and tried it and had all kinds of oil leaks that weren't there before the synthetic stuff. Switched back to a normal motor oil and the leaks were gone.....

The synthetic stuff is good for a lot of the higher performance engines in sports cars and some large trucks/hauling vehicles.... but normally the manufacturer will build the motors in those so that you need to use the synthetic stuff.

With the age of your vehicle, it can't hurt to use the high milage stuff, but you don't need the synthetic.... save the cash and take your Mom out to dinner to say thank you for giving you a car....

[Will Hay]

....he was right in my case. I didn't listen and tried it and had all kinds of oil leaks that weren't there before the synthetic stuff. Switched back to a normal motor oil and the leaks were gone.....

Man, that's just made me realise something.
I have a 1971 MG B Roadster and have been buying the expensive/synthetic stuff too.
I always had to put up with a front end leak but recently, having run out of the synthetic stuff went back to the cheap stuff.
That regular patch on the garage floor isn't as bad as it once was, I noticed it last week.
Will

[John James]

Im not sure if this question has been asked before, if it has pardon me...I would like to know if synthetic oil for a car would be beneficial or not.
VTM

I wouldn't use synthetic oil and this may upset and damage the motor. I don't think synthetic oil is made for your car.

Better to use normal, proper oil for your old car as the motor can get pretty hot. Use regular oil will help to prolong life of the engine.

For an old car, your must also check for level of oil in the motor vehicle as leaks can happen.

I sold my 24 y.o. car two years ago.

[rallynavvie]

Just to put to rest any fallacies...
All motor oil, be it synthetic or organic or blend, has a viscosity and weight rating right on the label. So 5W-30 synthetic is not going to find leaks any more so than an organic 5W-30.

However it is true that many organic engine gasket materials will break down faster from synthetic oil usage, but these are only found in older models (such as your MG unless you put newer gaskets in it). This is where the idea that synthetics would "find leaks" when used on older models as it was essentially causing the leaks. Also it isn't a good idea to switch from one and start using the other, it tends to muck things up. If you've been running regular oil just keep using it (unless you've built up your engine). If you've always had synthetic in it just keep running synthetic. My car has been using Mobil One since it came from the factory and since it regularly sees track time I don't think I'll be using anything else.

A few advantages of synthetic:
- better viscosity in cold weather making cold starts a little easier
- less break-down at extremely high operating temps so more stable in performance cars (i.e. track cars, not the slushbox you think is fast)
- less intrusive residue clinging to engine parts
- cleaner when using a proper filter (no more coked-up turbo bearings... well, slightly less often anyway)

[fmctm1sw]

I remember reading something about all the molecules being the same size and that is somehow beneficial...

[indolikaa]

For what it's worth...

I have an '87 Dodge Ram with a 2.0L 4 and 165,000 miles. Been in the family since we bought it with 3 miles on the odometer. Runs 10W30 in the summer and 10W40 in the winter. Good-ol' fashioned Wal-Mart cheapo oil. Been burnin' 1 quart of oil per 3,000 miles since the early 90's. Still gets 30-33 MPG.

I also have a '02 GMC Sonoma with a Vortec 4400. It runs on either gasoline or ethanol; it's one of them fancy FFV engines and only uses 5W30. The dealer recommended a synthetic blend because of the engine's FFV engineering. He could've been talking out his ass for all I know, but I keep a supply of the Wal-Mart red bottles on hand anyway.

[gmatov]

Unless you're a little bit backward, you DO mean 10-W-30 in the Winter, 10-W-40 in the Summer?

Cheers,

George

[luvvbuzz]

i was always told that fully synthetic oil is more high performance than mineral oil, because it was specially formulated for the job and there for tailor made. also i used to ride a suzuki rgv 250 which is a 2 stroke motorbike. as it was a high performance 2 stroke engine it was always reommended that synthetic oil was used as it left less deposits behind and therefore the engine did not get coked up so quickly. i know that is not to do with cars but i just think that synthetic oil has more benifits than traditional mineral oil.