Over the years we are all familiar with how much plastic is being used in the engine components, thermostat and coolant junctions along with inlet manifolds and radiator end and header tanks. Now another piece of plastic is creeping into the engine build and that is the sump drain plug.

This 2016 Mercedes C220 AMG had a plastic sump drain plug. The plug is not threaded but has a bayonet type fixing and only needs half a turn to remove completely from the sump. This will not nip up but will only tighten to sit in one place and with a torque setting of only 4Nm this feels strangely low when tightening up.

Reassuringly the Mercedes sump capacity is still above the average at 6 litres, which is one of the reasons I believe the engines last so well.

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