An internal combustion engine having a camshaft which is translatable
between first and second positions to control an engine operating
characteristic. The camshaft is rotationally driven from the engine
crankshaft, and includes an oil pump member in fluid communication with
the oil sump of the engine. During rotation of the camshaft, the oil pump
member pumps oil from the oil sump to various lubrication points in the
engine, and also generates an oil pressure which acts upon at least a
portion of the camshaft. At low engine speeds, the oil pressure is
insufficient to translate the camshaft. However, at high engine speeds,
the oil pressure is sufficient to translate the camshaft axially during
running of the engine, and the camshaft returns to its initial position
when the speed of the engine decreases. Translation of the camshaft may
facilitate an automatic compression and/or vacuum release feature, a low
and high speed cam switching feature, or a low oil shutdown feature, for
example.