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If the car is brand new, follow the manufacturers recommendation. I believe it's around 3,000 miles.

Do not change it (1) sooner than that or (2) sooner WITH synthetic oil. Doing either of those things will extend the engines need for break in as you will not allow the parts, such as valve seals, rings, etc., to seat properly and provide a healthy seal which your engine depends on for a long life.

If you do not know the manufacturers recommendation, better call your dealer. Generally, the new cars come with a sticker on them, mine did, and follow the directions there.
 

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2003 2.5 rs
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Discussion Starter · #3 ·
thank for the info the reason why i ask is that people posting on ebay saying that they first changed the oil at 500.
 

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I don't know the exact number, but I DOUBT it's 500 miles. It should be more like ... um... I think it was 2,000 miles on my RS.
 

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if the car is brand new, Subaru says 1000 miles. this is because they use a special oil designed to help everything seat properly (the aptly named break-in oil). its not the greatest for engine protection which is why you shouldn't rev above about 3k.
 

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10th Warrior said:
if the car is brand new, Subaru says 1000 miles. this is because they use a special oil designed to help everything seat properly (the aptly named break-in oil). its not the greatest for engine protection which is why you shouldn't rev above about 3k.
There's been some debate on this topic and I finally went to my local service department and asked the head guy there and he said the "break-in oil" is a myth. They use regular old dinosaur oil. So I would strongly disagree with that.

In addition, http://my.subaru.com says the first oil change is at 3,000 miles.

Subaru STi owners manual said:
New vehicle break-in driving
– the first 1,000 miles (1,600 km) The performance and long life of your vehicle are dependent on how you handle and care for your vehicle while it is new. Follow these instructions during the first 1,000 miles (1,600 km):

Do not race the engine. And do not allow engine speed to exceed 4,000 rpm except in an emergency.

Do not drive at one constant engine or vehicle speed for a long time, either fast or slow.

Avoid starting suddenly and rapid acceleration, except in an emergency.

Avoid hard braking, except in an emergency. The same break-in procedures should be applied to an overhauled engine, newly mounted engine or when brake pads or brake linings are replaced with new ones.
And here's the technical details on breaking in an engine.

GREAT ARTICLE: http://www.stealth316.com/2-breakin.htm

The first few hundred miles of a new engine's life have a major impact on how strongly that engine will perform, how much oil it will consume and how long it will last. The main purpose of break-in is to seat the compression rings to the cylinder walls. We are talking about the physical mating of the engine's piston rings to it's corresponding cylinder wall. That is, we want to physically wear the new piston rings into the cylinder wall until a compatible seal between the two is achieved.

Proper engine break in will produce an engine that achieves maximum power output with the least amount of oil consumption due to the fact that the piston rings have seated properly to the cylinder wall. When the piston rings are broken in or seated, they do not allow combustion gases to escape the combustion chamber past the piston rings into the crankcase section of the engine. This lack of "blow-by" keeps your engine running cleaner and cooler by preventing hot combustion gases and by-products from entering the crankcase section of the engine.

Excessive "blow-by" will cause the crankcase section of the engine to become pressurized and contaminated with combustion gases, which in turn will force normal oil vapors out of the engine's breather, causing the engine to consume excessive amounts of oil.

In addition to sealing combustion gases in the combustion chamber, piston rings must also manage the amount of oil present on the cylinder walls for lubrication. If the rings do not seat properly, they cannot perform this function and will allow excessive amounts of oil to accumulate on the cylinder wall surfaces. This oil is burned each and every time the cylinder fires. The burning of this oil, coupled with "blow-by" induced engine breathing, are reasons that an engine that hasn't been broken in will consume more than its share of oil.

When a cylinder is new or overhauled the surface of it's walls are honed with abrasive stones to produce a rough surface that will help wear the piston rings in. This roughing up of the surface is known as "cross-hatching". A cylinder wall that has been properly "cross hatched" has a series of minute peaks and valleys cut into its surface. The face or portion of the piston ring that interfaces with the cross hatched cylinder wall is tapered to allow only a small portion of the ring to contact the honed cylinder wall. When the engine is operated, the tapered portion of the face of the piston ring rubs against the coarse surface of the cylinder wall causing wear on both objects.

Each tiny groove acts as the oil reservoir holding oil up to the top level of the groove where it then spreads over the peak surface. The piston ring must travel up and down over this grooved surface, and must "hydroplane" on the oil film retained by the grooves. Otherwise, the ring would make metal-to-metal contact with the cylinder wall and the cylinder would quickly wear out.

However the ring will only ride on this film of oil if there is sufficient surface area to support the ring on the oil. When the cylinders are freshly honed the peaks are sharp with little surface area. Our goal when seating the rings on new steel cylinders is to flatten out these peaks to give more surface area to support the rings, while leaving the bottom of the groove intact to hold enough oil to keep the surface of the cylinder wet with oil. See illustration. At the point where the top of the peaks produced by the honing operation become smooth and the tapered portion of the piston ring wears flat break in has occurred.

When the engine is operating, a force known as Break Mean Effective Pressure or B.M.E.P is generated within the combustion chamber. B.M.E.P. is the resultant force produced from the controlled burning of the fuel air mixture that the engine runs on. The higher the power setting the engine is running at, the higher the B.M.E.P. is and conversely as the power setting is lowered the B.M.E.P. becomes less.

B.M.E.P is an important part of the break in process. When the engine is running, B.M.E.P. is present in the cylinder behind the piston rings and it's force pushes the piston ring outward against the coarse honed cylinder wall. Piston rings are designed to take advantage of the pressure and us it to push the rings out against the cylinder wall. Therefore, as pressure builds during the compression stroke, the rings are pushed harder against the cylinder wall which aids in seating the rings.

The higher the B.M.E.P, the harder the piston ring is pushed against the wall. The surface temperature at the piston ring face and cylinder wall interface will be greater with high B.M.E.P. than with low B.M.E.P. This is because we are pushing the ring harder against the rough cylinder wall surface causing high amounts of friction and thus heat. The primary deterrent of break in is this heat. Allowing to much heat to build up at the ring to cylinder wall interface will cause the lubricating oil that is present to break down and glaze the cylinder wall surface. This glaze will prevent any further seating of the piston rings. If glazing is allowed to happen break in will never occur. Also, if too little pressure (throttle) is used during the break-in period glazing will also occur.

Most people seem to operate on the philosophy that they can best get their money's worth from any mechanical device by treating it with great care. This is probably true, but in many cases it is necessary to interpret what great care really means. This is particularly applicable when considering the break-in of a modern, reciprocating engine.

For those who still think that running the engine hard during break-in falls into the category of cruel and unusual punishment, there is one more argument for using high power loading for short periods (to avoid excessive heat) during the break-in. The use of low power settings does not expand the piston rings enough, and a film of oil is left on the cylinder walls. The high temperatures in the combustion chamber will oxidize this oil film so that it creates glazing of the cylinder walls. When this happens, the ring break-in process stops, and excessive oil consumption frequently occurs. The bad news is that extensive glazing can only be corrected by removing the cylinders and rehoning the walls. This is expensive, and it is an expense that can be avoided by proper break in procedures.

We must achieve a happy medium where we are pushing on the ring hard enough to wear it in but not hard enough to generate enough heat to cause glazing. Once again, if glazing should occur, the only remedy is to remove the effected cylinder, re-hone it and replace the piston rings and start the whole process over again.

We asked four top motorcycle engine builders what they do to ensure peak power output and optimum engine life. Here is a capsulation of their responses.

"If the wrong type of oil is used initially, or the break-in is too easy, rings and cylinders could (read will) glaze and never seal properly. A fresh cylinder wall needs some medium to high engine loading to get the piston rings to seat properly for good compression but make sure you don't lug or overheat the engine. Use high quality, low viscosity oil (Valvoline 30 weight), no synthetics, too slippery. If synthetics are used during initial break in the rings are sure to glaze over.

An engine's initial run should be used to bring oil and coolant (air, oil, and/or water) up to operating temperature only, with little or no load, then shut down and allowed to cool to ambient temperature. This is important. After each run the engine needs to completely cool down to ambient temperature. In Texas, especially in the summer, that's still pretty hot. After a cool down period, start it up again and take the motorcycle for it's fist ride (you hope).

This time give the engine light loads at relatively low rpm and stay out of top gear. Lugging the engine, i.e., low RPM with a lot of throttle (manifold pressure), is more detrimental than high rpm. Another key is too constantly vary engine load during the entire break-in period. A constant load is not ideal for breaking in bearing tolerances. This second run should last only 10-15 minutes before another complete cool down.

The third run should see slightly higher rpm with light to medium power loading using short bursts of acceleration to help seat the rings. Again 10-15 minutes of running should do it and again avoid top gear. A forth run should consist of light to medium engine loads with a few more bursts of medium-high rpm, and lasting just 10-15 minutes varying the engine load and again avoiding top gear. Next while the engine is still warm drain the oil and change the filter. This gets out the new metal particles that are being worn away. Most of the metal particles will break away within the first 50 -75 miles. To ensure the rings seat well, use the same high quality oil and don't be shy about short duration high rpm blasts through the lower gears after the oil has been changed.

A few more 15-20 minute sessions should be used to work up to the engine's redline gradually increasing the engine loads. After some definite hard running and 250-500 miles it's a good idea to check the valves. After 500 miles re-torqueing the head is suggested. Switch to synthetic oil but not before 500-1500 miles. Most of the engine experts warned of the danger of breaking in the engine too easily and ending up with an engine that will always run slow whether it is from tight tolerances, inadequate ring seal or carbon buildup. Engine load is more detrimental than rpm because of the head created internally, so avoid lugging the engine but rev it freely especially in the lower gears. Basically, be sure not to get it too hot but be sure to seat the rings properly.

So that's it, sure a lot different than keeping under 4000 rpm for 500 miles then under 5000 rpm for 1000 miles. Maybe bike manufacturers are being super cautious at the expense of your motor's performance? I think that they take the cautious route that works over time (1000 miles, or about 20 hours of break in) versus a faster route that can be more easily screwed up."
 

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Scoobymods Guy
2010 Legacy 3.6R Limited
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That's some good info. You mind if I copy it and post it on our Scoobymods site?
 

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Feel free, since I copied it from somewhere else... :eek:

Sticking this since it seems to keep coming up... :D
 

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Well... I certainly feel better about bouncing off the rev limiter in 3rd gear passing a Buick on a back road with ~400 miles on...

:eek:
 

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Only problem with that theory is there are cars that come from the factory with Mobil 1 and other synthetic oils already in them, the MINI Cooper is one example.

The owners manual states 3 months or 3,000 miles as the time frame for the first oil change. I'll be hitting the 3 month interval at around 2,000 miles. I plan to switch to synthetic at my first oil change. My Subaru service department manager said it won't be an issue.

Bill
 

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Scoobymods Guy
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wgb113 said:
Only problem with that theory is there are cars that come from the factory with Mobil 1 and other synthetic oils already in them, the MINI Cooper is one example.

The owners manual states 3 months or 3,000 miles as the time frame for the first oil change. I'll be hitting the 3 month interval at around 2,000 miles. I plan to switch to synthetic at my first oil change. My Subaru service department manager said it won't be an issue.

Bill
Some cars come that way because they were pre run and broken in with dino oil at the factory like the Corvette.
 

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Peaty,

WOW!! So "brand new" cars like the new Cooper have engines that have already been run-in? Do the odometers reflect this?

Bill
 

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Scoobymods Guy
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I don't know if they do it w/ the Cooper or not. Like I said though Corvette and I think Porsche do this and no they do it on a bench not while it's in the car. At least that's what I was told by someone that worked in the oil industry developing base stocks.
 

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Interesting note...
Although I dunno if I was told bollucks...
But according to the Subaru lady,
when I picked up my 04, they run them in 3,000 kms on a Dyno and then do the first service for you.

And no the odomoter was not affected...

Of course I dunno what year they started doing it, and/or whether its AU only.

I also got told, when I rang up with fairly low oil, that these engines burn oil...
Is that correct?
Cause my last car (1982 Holden) didnt burn oil, and it was ancient.
 

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That lady is smoking CRACK. They don't dyno them, sorry. I've done plenty of research. You are welcome to email Subaru directly and they will also let you know that is false.

Think about it - manufacturer recommended break in period is in every car. Why would they put that there if you didn't have to do it? Yeah...

They burn oil if you don't break them in properly, that's for sure! My 2000 RS did not burn any oil at all.
 

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so when purchasing a used car a good question to ask the previous owner is if it burned oil? since i read this last year i've been very concerned about how vehicles are/were treated when brand new. and that brings me to think and cringe about the 3 STIs down at my local dealer (and any other new car on any other lot) that have their keys handed to just about anyone daily. i mean, how are you gonna test drive an STI with 20 miles on it? redline?...uh...YES!
so my concern is how are we going to know if an engine has been broken in correctly or already trashed???
 

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Hmm... Now Im concerned... (a little...)
Perhaps I'll see about a 6,000K service....
Even tho they only recommend one every 12,500kms... (or perhaps try it myself... :p )
 
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RS25.com said:
......They burn oil if you don't break them in properly, that's for sure! My 2000 RS did not burn any oil at all.
Mine doesn't with 61K on the clock now.

I changed the oil and filter at 500, 1000, 2000, 3000 miles with 10-30 dino Valvoline. At 4000 I went to Mobil 1 and have been with it every 2500-3000 since, even if it didn't "need" it. Lots of oil changes!

Durring the first 4000 miles, I never used the cruise control, and when on the highway I fluxuated my speed in 5th up and down a few MPH. I'd rev to 4000, never over 4500.

Now I can do anything in any gear (well, 1-3) and no oil ever gets sucked/used/burned EVAR! :D

My understanding was that contaminates do nothing for break in, and if anything new motors will restrict a filter with gunk faster, lowering pressure and volume from the oil pump. I think in a warm climate that never gets below 40*F one should use single-grade oil for break in, but if it gets damn cold like it did when my motor was new, a light multi-grade is better. I could totally be wrong, but my engine seems to like it.
 
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