See also:

Ford Sierra Service Manual
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Engine oil and filter renewal (Every 6000 miles or 6 months)
1 Frequent oil and filter changes are the most important preventative maintenance procedures that can be undertaken by the DIY owner. As engine oil ages, it becomes diluted and contaminated, which ...

Cylinder head - removal and refitting (engine in vehicle)
Note: Refer to the warning at the beginning of Section 5 and the note at the beginning of the following Section before proceeding. The cylinder head must not be removed when the engine is warm. R ...