Synthetic Oil ??

I only use full syn in my Subaru. I used it in my previous vehicle. I will use it in any vehicle I buy in the future. Maybe it makes a difference maybe not, but I keep my vehicles a while and have never had an engine/oil issue in any of them.

If you google 'synthetic oil' on this newsgroup you will find thousands of opinions on the advantages/disadvantages of synthetic and dino oils.

It's been 'done to death' a number of times.

Here is a good article about oil. It relates to oil in air cooled boxer engines in Porshes but ilustrates the issue of weakening anti-wear additive packages in newest SM designstion oils (current formulatuions seem to prefer mixtures best for fuel economy and catalitic converter life).

Those who take their cars to the track may benefit directly.

I like to use synthetics when the car is fairly new, say up to 100-150k miles and then swith to regular but slightly thicker oil, and change it very frequently, then. On an old loose engine blow-by contaminates new oil much too fast to make synthetics very economical. Also leak problems are common which regular oil can patch somewhat.

M.J.

Interesting that shops are switching to Mobil's syn motorcycle oil. I run Mobil1 4MT Racing 4-stroke motorcycle oil in my airplane per the manufacturer's recommendation. A little too pricy for the Subaru at $11 a quart.

I use it but doubt that it is necessary. If I were on a tight budget I certainly wouldn't. However, it gives me a little margin if I'm a few hundred or even a thousand miles late on an oil change. It keeps varnish suspended better (that's why its always so dark coming out I think) .

In Texas, it gets very hot. I've seen owners manuals from a coupla cars in the past that described 'severe service' as continued operation above

90degrees!!! That's like 1/3 of the year here! lol! I intend to run Rotella 5w-40 in the summer and probably walmart's 5w-30 in the winter. Or perhaps Mobil 1. I don't put many miles on so the oil will probably only see about 4K miles anyway.

Carl

I use a synthetic blend. Cheaper than full synthetic. Tires Plus uses it as their base oil (no regular oil) and the oil/filter change is the same cost. I don't get it to reduce the startup ticking valve noise (hard to tell if it helps). I get it because winters can be cold here and the engine turns over easier.

Don't you have a turbo, and don't you think it is better for them? I beelieve Sube runs coolant around the turbo bearing, but still there's extra heat, especially after shuting the motor, which can be extreme.

A friend said that Consumers Reports said, it isn't worth it. I didn't read the story, and maybe not for a non turbo motor, unless maybe there are situations caused by the motor design. When synthetics first came out, Popular Sicence or Mechanics did a study with highway patrol cars in WI or MI, and ran them for 150K mi. The mineral oil was changed when recomended, and the Synthetic wasn't changed, and after

150K, they said the synthetic oiled motors had half the wear.

Oil is strange, like they say it never wears out, just the additives do, and then combustion, condensation, and gas that can get into it, can affect it. FI is supposed to eliminate or minimize the raw gas that can get in to when warming up. How ones drives a car, and the weather can make situations different. I just plan to use the Sube on long trips, but if it was my only car, it would be going on short trips, a mile at a time, and sitting for a while. I like to get the motor up to temp, every time it is used, thought that may not be anough, driving a mile, even if stopping often for lights and stop signs, but better than not.

Is the color of the oil varnish, or dirt and soot from combustion? I like flushing the old oil by pouring a little kersoscene in, after draining the oil, to get as much old stuff and dirt out, as I can. Not sure if keroscene is as compatiable with synthetic.

I read that oil may protect better the older it is, to a point, so recomended 7500mi between changes. I usually went by color, as to how well it might be lubing, when I changed it. Not a good test, but an indicator.

VF

I assume you are talking about teh same weight oil with the starting. I had an old car that was using some oil, and put the cheapest Straight Weight oil in it. When it started to get cold, the motor cranked like the battery was weak. Then I remembered I had the straight weight in it. ))

I have wondered if the blends were any better than straight mineral oil, since it is in it, and seems like they might be a weak link.

VF

VF

Letting the motor sit at idle before driving can contribute to fuel dilution of the engine oil (cylinder washdown). Something turbo Subie's are reknowned for. Just drive away gently instead, you'll use less fuel overall and contribute to global warming and pollution less.

The "dino" oils of today are head and shoulders above those of yesterday. Unless you have a turbo engine or live in extreme cold temperatures, "dino" oil will do very very well in a Subie. Since all their fours use a timing belt, oil stress is minimal in these engines. If you want to waste your money on sythetic, the oil co's will love you.

what does a timing belt have to do with stress on the oil?

The temp on my 2.5i comes up pretty fast so far in the summer. It is new, and I like to see the gauge move before driving. I believe in driving slowly as opposed to warming a car up completely. My dad didn't, but he lived too long with the single weight oils, and wouldn' t change his beliefs. Piston slap in a Sube, makes me want to go a bit slower, and keep the revs down till it reaches operating temps.

VF

I definitely 'try' to let my engine idle for 15 seconds or so before pulling out in the mornings or if it hasn't been driven in a few hours. And I 'try' not to hammer it to redline unless it has warmed up to normal operating temps. And yeah - supposedly the synthetics would resist 'coking' better so the turbo bearing 'may' get a little more protection.

Carl

You "MAY" (that's a big may) get some advantage. I have had no turbo or fuel related problems with a 90 GT Legacy wagon I had for 8 years and now on to a 02 model. I only used dino oils.

These guys at FHI have been designing turbos for quite a few years now and the initial design considerations would take into account the housewife (are you still allowed to use that terminology) who uses a car for a number of short trips every day through to the numbskull who only knows that that there is a go pedal and a stop pedal and every now-n-gain you have to put in some petrol from one of those pump things.

Doesn't matter what numbers are on the side of the pump as long as it says 'Petrol'

In otherwords they have to design them to be as idiotproof as possible and no presentday manufacturer can afford to put out a product that hasn't been overengineered by at least 50%.

Hate to bring up a touchy subject, but don't, or didn't Subes have a head gasket problem, that could be catastrophic? I'd like to protect things that I could, and with turbos heating the oil to a much higher temps, and synthetic handling higher temps, it seems logical to use it. If something was doubtful, I'd flip a coin, and then decide for myself.)

VF

Less oil shear.

You are wasting fuel and adding to air pollution if you are idling it in order to 'warm' it. The engine oil is more viscuous when its cold, and provides ample protection in a cold engine with its looser clearances. And it is designed to be driven cold. If you have audible piston slap in a new Subie you should get it fixed under warranty. Try to keep the air we must all breath as clean as possible, will you? Think of your children, and their children, and..... If you're going to be that obsessive about engine temp, then use synthetic oil and skip the silly warm-ups. All you're accomplishing is faster glacier melt.

The HoundMan very likely does not have children given the amount of time and energy he spends posting here and working on his new baby. This would explain his fuel usage habits.

cough..cough..

so warming a new engine a bit is gona melt a glacier? Fragile aren't they? My old Chevy Daily Driver probably polluts 100X more, though in a BIG city with 3 refineries up wind, it probably cleans the air.

I Thought piston slap came with wear, and a cold engine driven hard. Must be mistaken.

FV

I Thought there were people here who Knew about Sube's, and modern machinery. I got cut off at the knees in 88' from a devistating injury, including brain, liver, kidney, lung, vision, hearing, and muscle damage, Kids are long gone and the wife is dead, so trying to remember the Old, and catch up on the New. Some people Know and Don't mind sharing, like I do when I Know something, and others just flap their jaws, and say Nothing.. It takes All Kinds..

I've had the car a month, and hardly did anything that I planned to. Cooler weather hopefully will get me moving. Added an alarm today. Better not talk about it, some people don't like to Hear others did things, or want or plan to. Makes them feel inadequit or lazy. Takes me 10X longer than it should, If I can do things, but I won't give up wanting to and trying. Even if neighbors tell me I make them tired just watching me, but they always said something when I was up to my elbows in pisons and valves. Drove a machinist to Auto Shop classes to Learn how to work on his car, though didn't last long. Now he still says what I'm doing are Good ideas, and he Wished he had done them. It Takes All Kinds...

FV

Piston slap is likely gone or much reduced in today's soob engines. They had a run (Rick - anyone?) several years ago where, in an effort to reduce recip. mass or meet ever-stringent pollution requirements/whatever, the pistonds had skirts which were too short.(and maybe the wrist pin placement was different? not sure). I haven't noticed any noises from my 2 soobs. Though they are 03 and 06 . Older ones - yeah, they exhibit it.

Carl