Knocking noise from bottom end – rod bearings?
2010 2.0 TDI Passat has a low knocking at idle when warm, gets louder under load. Oil pressure okay, no metal in filter yet. Suspect big end bearings worn. Planning to drop the sump soon- should I inspect crank and block while in there? Any common issues on these engines?
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That knock is classic rod knock on PD/TDI engines from bearing wear- often from infrequent oil changes or diluted oil. If caught early, bearings can be replaced without full crank damage, but always check journals for scoring and block for cracks around mains. I did a bottom-end refresh on mine after similar symptoms- measured crank with micrometer, polished journals lightly, new bearings all round. Sourced main and rod bearings plus thrust washers from https://elartcom.eu/categories/engine-block-and-crankshaft-141 - they have sets for VW 2.0 TDI (including undersize options if needed) and some crankshaft pulley/damper parts. Bearings were good quality, tolerances spot on. Knocking gone completely after reassembly with plastigauge check. No more noise even at highway speeds. If you're opening it up, grab a crank pulley tool too if yours is worn. Their category covers block-related bits well- check engine code for exact match.