There was a trend (started by VAG and eagerly followed by others) for service schedules to be written by the marketing men... to appeal to fleet owners... ...after calculating that problems weren't likely to occur within warranty, naturally.
But I hear that VAG have pulled back to 10,000 mile intervals now... make of that what you will...

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'98 M2 Razorback, it's a keeper.

I confess that I tend to fret over such things. If in doubt I would drain the XB swing arm and replace with an equal amount of new oil just to take on a warm up run. Then drain and replace all with the filter on my return. Oil is cheap....or was!

My little Nova car has done all its 181,000 miles on good old mineral oil plus a shot of Wynn's. Can still cruise near its maximum and does not smoke or burn oil. I do change the oil every 4500 miles though! Wynns is amazing stuff, but you have to get the % right.

Why do race teams always put new oil in every meeting?

It is the additives that make a good oil, detergents that keep the engine clean by making sure the contaminants stay in suspension until the oil filter can remove them, viscosity stabilisers that well stabilise the viscosity etc ........ the main thing is to use the correct type of oil for your engine and remember that it is the journeys where the oil doesn't get up to full temperature that does the most damage because you then end up with condensation in your engine which gets mixed with the oil. This is another reason why you should never just start an engine for a few minutes once a week/month during the winter , spin it over on the starter to throw some oil around inside if you must but do not start it unless you are going to get the complete engine including fluids up to full temp.
My petrol Mondeo which uses a 2litre mazda engine has done 117K and gets a service and oil change once a year and oil consumption is negligible (think I've bought about 3 lyrs of top up oil in 10 years )

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2001 X1 2009 1125CR 2006 Uly X3 2010 Uly a fully Maz'd S1 and a 1991 RS1200 Westwind.

are lyrs bigger or smaller than litres

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Buell Ulysses XB12X 06/08