AndyS44

Run in carefully, semi synthetic at 1k servce etc etc.

....Considering mid service oil change (UK 10k service interval)??

Will go for one of the big three oil recommendations (motul/mobil/castrol) - Do I need to change filter every time? would it be stupid not to? How often is optimum to change oil??

dnb

Always change the filter with the oil - it doesn't cost much. Use a genuine Subaru one if your car is under warranty.

As for the frequency, it depends on how hard you drive the car, length of runs you do etc...

I change the oil in mine every 4k (approx) as I seem to do loads of short runs.

AndyS44

Run to work is about 45 mile round trip. So in the main it gets nice and warm most of the time.

Was going to change at 5000 miles interval?

Where is best for Castrol RS /Mobil 1 motorsport / Motul Fully synthetics??

What sort of price are they? Castrol seems to be the cheapest at about £20 (scoobyshop)??

TBMeech

I change mine religiously every 3,000 miles, ALWAYS use a Genuine Subaru filter regardless of how often you change the oil, it's well known that there have been plenty of engine faliures from using aftermarket filters.

barge

As TBM

I do it every 3000 miles

Gez

I would rather follow Subaru Japans advice and change the oil between 2500-3000 miles rather than the UK specified intervals.

Cheers

Gez

DO'B

My company repairs large numbers of Subaru engines avery month and we advocate an oil change every 3000 miles, changing the oil filter at the same time with another genuine one. HOWEVER, what you must do, is fill the oil filter with oil before fitting it as the short time run between the engine starting and the oil pressure building up does untold harm the the big ends and we all know about them - don't we?

We also recommend disconnecting the ignition module connection - N/S cam bank, top cam connection, about 5-6inches back from the cam cap. before turning the engine over anyway, so that the unit will not start. When the oil light is well and truly out re-connect and start. Remember idling speed [ whilst the oil pressure is building up] is maybe 700 RPM on a good day but that's still over 11 times per second - DRY !! think about that over the number of oil changes in a units' life and you'll find your beloved engine has run dry for nearly half a minute - Hmmm

After a good run in of a new engine, any top quality silicone oil is perfect. Until run in properly from new or rebuild use a standard non silicone oil. Silicone is very slippery and a run in requires friction to bed the parts in. Prevent the running in friction and you'll get shiny bores and oil consumption.

AndyS44

Cheers DOB,

3k miles seems like the 'official' figure to change. But why? using the same thought process 2k would be better? Where has this magical 3k figure come from?

Also, you mention bearings running dry - now it follows to fill the filter, but does oil drain from feed oilways and bearings??

I thought they would remain pressured by the pump??

Please advise.

AndyS44

bttt

stockcar

as long as the service is carried out properly (and dependant on use) we normally recomend 5K interval as any shorter than this and you are getting no benefit from modern fully synthetic oils (also bear in mind proper weight oil is just as important!!!!)
pers recomends are either Silkolene or Millers (deals on both to scoobynet)

having said the above we change the oil on some of our competition cars every 80-100miles due to heat soak and contamination of "anti-lag"
alyn - as performance