Transit engine using excessive oil

My Ford Transit is using excessive oil, approx 1-litre per week. It's done 105,000 miles, mostly long distance, but since I've had it it's used for short local journeys. there's no excessive smoke and no leaks. Any ideas?
Likely to be either the turbo bearing oil seal or the valve stem oil seals. No excessive smoke suggests more likely valve stem oil seals.
Answered by Honest John on

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