I can't see why a normally aspirated 1.5L 4 cylinder japanese boxer engine should have drastically different service requirements to an inline 4 cylinder japanese engine.
You should do the following at the 100,000km service
- Change engine oil and oil filter
- Replace gearbox oil / automatic transmission oil
- Change fuel filter
- Change air filter
- Change spark plugs
- Check engine timing
- Clean fuel injectors
- Flush out and replace power steering fluid
- Flush out and replace coolant
- Flush out and replace brake fluid
- Flush out and replace clutch fluid (if equipped with manual transmission)
- Replace timing belt and tensioner
- Replace all drive belts - alternator, air-conditioning and power steering
- Check over suspension and tighten/replace whatever is necessary
- Check brakes and replace as necessary
- Check wheel balance and alignment
- Replace a/c cabin filter
You would in all likelihood get a more informed response from the Subaru forum on this website.
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