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Discussion Starter #1
I was wondering how many of you guys use synthetic motor oil, since it is designed for driving under extreme conditions? I often find myself in these extreme conditions :D, so I was wondering if I should switch to synthetic.

Thanks

Alex
 

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I've been using Mobil 1 (full synthetic) since about 10k miles in my 99RS.

Whether you should switch or not is up to you. Some swear by synthetic, some swear that Subarus don't like synthetic, some say it's fine as long as you wait till 7.5k-15k miles to change it to synthetic.

I went with the third option and haven't had any issues thus far (about 34k total miles on my car).
 

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To tell you the truth I really don't think it would matter. I have an 86 Celica with a million miles and runs great and it has never seen synthetic. And since break-in I have used nothing but Mobil-1 in my RS with no problems. If you change your oil regularly it won't matter. If you do auto-x or run it hard often decrease your intervals to 2000 miles or less.
 

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AT 15K I went to the full synthetic Syntec ( I think its 5 W 50).....with summer temps of 100 to 120 and pulling a trailer for camping from time to time.....at 26K all is well.....
 

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OOOHOOH, I know,I know pick me!!!

I went thru the same debate. Did my own test on my 25RS and my buds Boxer ALFA Romeo. And found out for myself.

We tried Mobil and Valvoline (our favorite synthetics) 5w40 and 5w30. The test was done in mid winter of a very cold year avrage temp was 12 degrees F. Ran both oils with our favorite filter, Purelator (still a good filter in my opinion). Over a 3 week period we tested for cold starts to pick our best starting oil. It was mobile 5w30 worked good in both our cars. But the Valvoline 5w40 ran smoother at temp. So he ran VAL 5w40 in his car I used Mobile 5w30. In 5 winter months we ran both oils in our boxer engines in Frekin cold weather. Each did an average of 7200 miles. Results:

~At 500 miles oils ran better than when first fresh.
[email protected] 3500 miles oils started to brown.( My subie was pretty new but mine was darker.) Continued test. (NOTE: It was to freekinn' cold, didn't want to do any work on our cars yet.)
[email protected] 4200-4600 miles noticed a decrease in preformance. ( take offs, revvin, Hard to start, that could have been the cold) Oil was black in my car and Dark brown in the Alfa.
[email protected] 7000-7600 miles got sick of hard starts and bad revin. Drained oil changed filters. Temp was 30 degrees F. Oil was very black in both cars. Thick as molasses also got thick crust film around filters from cooked oil. "eyawza!!!" :eek:

Both of us put 5w30 normal cheapy oil in to help clean engines for 2000 miles.


Then switched to Amsoil 5w30, and I use sdf-36 (bigger) or sdf-34 (smaller) filters.

We never looked back :)

P.S. I became a dealer for the cost breaks not for profit!
The stuff works. Note if you have turbo use 10w30 or 10w40 (if you have an older car). The stuff is really lite and has the best protection. At 6000 miles the stuff starts to turn brown not black. I change my oil 2-3 times a year every 6,000 to 7,000 miles. It works great for both the Subaru's and the Alfa's Boxer engines.


Good luck

:biggest:
 

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Amsoil intervals...

EchoWrx,


You stated that you change the oil every 6-7K miles. Are you using the the ASL-5W30 synthetic oil which you only have to change once every 25K or the XL-7500 (I assume this one) which is 7500 mile changing intervals. And if you are using the XL-7500, why instead of the ASL-5W30?? (Note: both oils are of SAE 5W30 weights) IS there much of a difference between the two for performance or longevity in a performance car? (And I mean real longevity, not manufacturer's statement, hence the difference of stated intervals between the oils). Also, there is a High Performance oil by Amsoil called AMO- 10W40 (there is no 5W30 in this version) high performance synthetic oil, but Amsoil did not recomend this oil when I inquired about which is the best oil for the Sube under heavy highway use. They recommended the ASL-5W30. Any info would be helpful. Thanks.

- SubyScubyDoo
 

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I use the Amsoil 5w30 that lasts to 25,000. The XL stuff is good but for a dealer it is only a few cents cheaper. So I spring for the best stuff. 7000 mile oil changes are less than half the recommended interval for the stuff but if you do a lot of HAUL-ASS you would change your oil sooner too. Only the best in my cars.

I change my oil at these intervals because the oil is cheaper than a new engine :)

Even my dealer is a little miffed that I dont use the oil for the full 25,000 miles life of the oils worth. I tell him "Don't U like sellin more Amsoil for the rebates at the end of the month?" Then he smiles and nods :rolleyes: ;)

I also recycle the oil so it's not bad and it saves the enviroment with less oil changes. Also it saves me time under my car. It's more fun to drive :cool:

The AMO- 10W40 I am not to sure about, I don't have my current product & price list in front of me. In my opinion DON'T use this stuff in your Subie. I use Amsoil 10w40 in my 1GMC, 2FORD delivery trucks with an average of 150,000 miles between all 3 of them. This stuff works well but it is to thick for the subies unless you have 170,000 miles or more on your Subaru I dont suggest this stuff.

My Subaru friends use the Amsoil 0w30 stuff in their cars cuz it lossens the rev band up some or it is freer to rev but I think in a boxer engine you need some start up protection. (The engine is horizontal for GOD'S SAKE!!!) They laugh at me while they happily buzz away in their "SUBIE BEES"!!! Oh well to each their own...

Hope this helps.

E.C.

Where did you hear that the AMO- 10W40 should be used in a Subie??? :confused:
 

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Almost forgot

I use 5w30 weight oil all year (winter and summer). It works fine in cold temps because of the low freezing temp of the oil. It wont thicken up when it gets cold but protects well when it gets hot. I also have 38,000 miles on my Year 2000 2.5rs Subaru. :run:
 

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I'm one of those 'SUBIE BEES,' :lol: Actually, I didn't notice a difference when I did the change to Amsoil 0w30 Series 2000, so I'm jumping back into the 5w30 bandwagon. And I sure love the 6000-8000 miles intervals and still be as safe as the other oils changing at 3000 miles.

Heck, a courier services' Ford Aerostar hit 800000 miles with Amsoil and still running towards the million mile mark. Now that's imprezzive enough for me.
 

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EchoWRX,

Sorry I haven't answered back sooner, but July 4th vacation got in the way 8).

The 10W40 oil was listed as heavy duty oil for High Performance Engines and usage at the Amsoil online store. The official answer back from Amsoil was to use *only* 5W30 oil (which the high performance version was not made in) as it is the closest to approximate the oil recommended by Subaru. The question then raises, is why isn't the High Performance version of the Synthetic oil in this weight and what engines are suppose to be using it?? (A relatively high pressure four banger being modified for street and track use doesn't qualify then I'm not sure what does aside from a quarter million dollar single purpose race car!)

Also, wondered if the seals for the Impreza can handle the Synthetic oil after being used with organic for 30-50K?? Some aftermarket kits don't recommend the use of synthetics as it may cause the seals to wear out quicker, also annoying leaks can turn to bigger leaks) Any comments??

- ScubyScubyDoo
 

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Good Question...:confused: I like your thinking.

The words...

"High Performance (HP)" = "Heavy Duty" it should actualy read "for vechiel that have less cooling, hi heat, larger engines, bear hi stress loads equal to that of the weight of the vechiel times 2 and/or endurance run engines that run at high rpms for a non-stop extended period until the time of maintenence."

Our Subarus could fit into some catagories, but not all at the same time.

HUH?? :( What???

Relax I'll do my best to explain...

"HP" IS A SELLING TACTIC USED BY AMSOIL TO PERMOTE THIER OIL!!! :eek: Gasp!!!..., you say?

Well other companies do it too, its just that Amsoil can back their "smack talk" up with proof. (I hope ;) )

EchoWrx
 

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EchoWrx said:
Good Question...:confused: I like your thinking.

The words...

"High Performance (HP)" = "Heavy Duty" it should actualy read "for vechiel that have less cooling, hi heat, larger engines, bear hi stress loads equal to that of the weight of the vechiel times 2 and/or endurance run engines that run at high rpms for a non-stop extended period until the time of maintenence."

Our Subarus could fit into some catagories, but not all at the same time.

EchoWrx
Gasp!
 
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