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Duration with Synthetic oil


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I've done a few oil tests over the years, but rely on running cars around 200,000 miles with minimal cunsumption and great engine durabilty to justify oil changes every spring, typically about 12,000 miles. It's been successful on four different vehicles since 1980. I change to synthetic at 1,000 miles and follow the manufactures recommendations until the warantee is over, then go with spring or pre-summer changes. This is for normally aspriated engines only. We have our first turbo (Volvo XC90) and I'm not sure what I will do for it yet, but I have over 50,000 miles of warantee to figure it out.

 

YMMV,

 

Jack, putting on the Nomex suit before the flames start

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only thing i would ask is how are the rubo bearing cooled. If they are water cooled, just do what you are doing (it makes me cringe) if the are oil cooled, its no so much that the bearings are hard on the oil, but the bearings need all the help they can get to stay clean and lubrictaed. The turbo spins at 50,000 rpm or more and sees high tempertiures, and they are not cheap to replace.

 

 

Not to endorse anything but this explains it well

 

http://www.performanceoiltechnology.com/syntheticoilandturbochargers.htm

 

nipper

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This is my last response to this thread, as im finding it is safer to talk politics and religon then oil.

Personally too many things can go worng with a car with long duration oil changes then can become a major problem if no caught early. An oil change interval of 3000-5000 miles is a good interval to inspect the car. Lets face it for most people, and form what i can tell here, a few here too, this is the only time the car gets looked at (we all seen threads that haves stated (gee such and such noise/cel light has been on for the last mont or two).

if the car has an oil monitor 9which i never stated nor assumed since not all cars have them) that i would trus only if it told me to change the oil sooner then i planned.

When i talk of failure, im talking catalysmic failure.Yes rungs wear, yes the oil sees alot of stress ta that point, but it is not acting a shock abosrober for 18, 000 psi of down force (actually its much higer then that, i just dont want to do the math right now). Every time you start the engine it suffers wear, but i have not seen a broken piston ring nor a sooby emiting a smoke screen. In fact cylinder wall wear using the recomended oil by the manufacutrere has been greatly reduced over the last 10-25 years. I cant even think of the last time i saw a heavy smoker, maybe 10 years ago.

I refuse to risk a 2500-3500 engine replacement for the cost of two more oil changes per year. yes you can figure it out and arugue cost all you want, but i dont want to be broken down on the side of the road with thrown rod at the most inoportune moment (murphies law). On these boards the biggest issue has been headgaskets then followed (not too often) by a main bearing failure if the engine has been baked.

As far as all oil having the same viscosity after 3000 miles, that was dino oil, that was true 15 years ago, but as with everything else time marches on, oil additives get better, chemistry gets better, and so does metalurgy, I dont care WHAT kind of oil you use, if you have a poorly designed engine to start with, its going to wear faster no matter what you do. With the advent of 100K emission warrenties, it is has forced better engineering of engines, better quality fuel, better quality oil, which in turn has made for longer lasting engines.

Now lets talk something safe like the new medicare drug programs ....

 

:lol:

 

 

nipper

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On the subject of oil: it is better to have crappy, worn out oil than nothing at all (and I have seen that all too often). I use a "frequent" schedule of 3K/change because it makes me feel safer when I can still see a bit of daylight through the oil when it is down to a 1/8" dribble as it comes out of the pan. I plan on tearing the engine down at 200K miles to check on the wear of the deep internals, and replace anything that is worn (not likely to be much, perhaps an HLA or two) as well as all gaskets/seals. When that is done, I will go to synthetic oil for the improved additives and detergents. what interval then? Probably the same. Sorry folks but I happen to agree with Nipper that a more frequent change interval is just good insurance against engine failure.

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but somebody posted a BMW engine run on the long intervals made possible by the lights that tell you when to change the oil. It was very sludged up which makes me think I will be changing the oil more frequently than demanded.

There may have been other factors like short trips for that Bimmer but why take the chance?

I am pretty busy just now but right after Xmas I intend to send my Mobil 1 extended oil to blackstone for analasis,and I think I may ask them what mileage I should change it to stay clean and well lubricated. Paranoia has usually made me change oil about 3,000 mile intervals.

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How about the question of time between oil changes?

 

What if you put 1000 miles a year on a car? (no short trips) Can you go 3 years between oil changes? ( I use Mob #1 exlusively)

 

How long is synthetic good with VERY low mileage?

 

Todd

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I would stick with a minimum interval of one year.

 

(Unless the car lives in a heated garage and only drives summer, on trips more than 10 miles - even then, once a year would still feel good, but if you're mileage was low you could stretch to two years.)

 

 

My personal view is that 3k miles is a waste of money and possibly extra loading on the environment.

I replace oil and filter at 6k miles, and that means every three months.

 

 

IF my mileage was lower, like 3k miles in 6 months, I would change oil then, but probably skip the filter to every other time. It's a question of balancing the time/mileage and factoring-in the number of cold starts.

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The standard answer is to change every six months if miles do not accumulate fast enough to perform a change based on mileage. I have two vehicles in this category, and I usually change them in late Fall and again in Spring. I had a truck which only saw about 800 miles a year, so I was doing 400 mile oil changes on it. The oil would drain clear. I once tried to go a full year with it and started to notice after about ten months that the oil light would take noticably long to go off when starting the first time in the day. I went back to six month changes just to be safe. This was with regular oil, but it still drained clear after ten months.

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An oil change interval of 3000-5000 miles is a good interval to inspect the car. Lets face it for most people, and form what i can tell here, a few here too, this is the only time the car gets looked at (we all seen threads that haves stated (gee such and such noise/cel light has been on for the last mont or two).

 

 

I agree; good point.

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At current prices, changing at 3k is an "acceptable" rationale for covering up potential engine problems that don't exist. How could anyone NOT see that?

 

Now triple the price of a quart and suddenly 7.5k seems like a perfectly reasonable and acceptable alternative to an extended drain (10k+).

 

It's the same way that a lot of folks suddenly "got religion" about fuel efficiency after the hurricanes.

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