E422HD86 Oil filter

Full-flow engine oil filter for MAN trucks with larger-displacement diesel engines, equivalent to MAN OEM 51055040122. Every drop of engine oil circulates through this filter on each pass through the lubrication system — its job is to strip out metallic wear particles, carbon soot agglomerates, and combustion by-products that would otherwise act as a lapping compound on crankshaft journal surfaces, camshaft lobes, and cylinder bores. The E422HD86 is a high-capacity format sized for D20 and D26 engines. Hengst manufactures the filter to the OEM bypass valve opening pressure and media efficiency class — both matter: a bypass valve that opens too readily allows unfiltered oil to circulate under cold-start conditions; media with insufficient efficiency allows fine particles through. Replace at every oil service — never extend the filter beyond the oil drain interval. Pre-fill the new element with fresh engine oil before installation to reduce the dry-running window for main and big-end bearings on first start. Before fitting, verify the old O-ring has been fully removed from the housing flange to prevent a double-seal leak.