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The oil in my Mercedes-Benz C200CDI is black after just 1500 miles. Does it need changing?

You repeatedly recommend to change the engine oil more frequently, ie every six months. On your website under 'Running in a diesel' you say "Leave factory fill of oil for the first year or 10,000 miles."

The oil in my new Mercedes-Benz C200CDI is black after only 1500 miles. Should I therefore continue until the first service in nine months time? Also, why would the oil discolour or contaminate in such a short time?

Asked on 9 September 2010 by Norman Winkler

Answered by Honest John
Carbon created inside diesel engines dyes the oil black. It still retains its lubricating properties.
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