Engine Rebuild / Replacement Engine Mercedes Benz 300, 320, 350 CDI OM642.868

OM642.868 engine overhaul — better than factory

The Mercedes-Benz OM642.868 is a 3.0-liter V6 diesel engine (OM642 series) that was installed in numerous vehicles from Mercedes-Benz, Chrysler, Jeep, and Dodge. The 300 CDI, 320 CDI, and 350 CDI variants impress with smooth running and performance — but suffer from typical weak points: oil pump wear, bearing saddle misalignment, and problematic cylinder bores inevitably lead to engine failure without professional intervention. MIK Motoren eliminates all known problem areas and overhauls this engine to a standard that clearly surpasses factory quality.

MIK upgrades — why this engine lasts longer

Our overhaul of the OM642.868 systematically addresses every known weak point of the OM642 series:

• Upgraded oil pump — The factory oil pump in the OM642 delivers too little oil pressure under load and at high RPM. This leads to rattling noises, error messages, and in the worst case complete engine failure. MIK installs a specially developed high-performance oil pump that reliably maintains oil pressure across the entire RPM and load range.
• Bearing saddle alignment — As mileage increases, the crankshaft bearing seats in the aluminum engine block of the OM642.868 shift. The result: the main bearings no longer run in line, leading to increased wear and engine damage. MIK hones the bearing saddle and permanently secures it in the correct position with hardened shims.
• High-quality bearing shells — All bearing components are precisely adjusted for optimal bearing clearance. High-quality bearing shells guarantee smooth engine operation and a long lifetime — even under high continuous load.
• Cast-iron cylinder liners — Depending on the model year, the OM642 was equipped with different cylinder bores: while the cast-iron variants are robust, plasma and AluSil coatings tend to develop scoring and compression loss even at low mileage. MIK uses only cast-iron cylinder liners for maximum wear resistance.
• LIVE documentation — Transparency as standard: Track the overhaul progress in real time through our project management app. Live images and detailed reports sent directly to your smartphone — no black box, just full control.

Scope of overhaul — nothing more is possible

• Main bearings, connecting rod bearings, thrust washers
• Pistons (for full overhaul)
• Piston rings
• Cylinder bores
• Connecting rods
• Crankshaft (for full overhaul)
• Bearing saddle (for full overhaul)
• Oil pump
• Timing chain kit (complete)
• Shaft seals
• Cylinder head gasket & bolts
• Sealing surfaces
• Valves, guides, stem seals
• Hydraulic lifters, roller rocker arms
• Camshafts (for full overhaul)
• Cam phasers (for full overhaul)
• Oil spray nozzles
• Stud bolts
• Pulley
• Oil pan
• Chain cover
• Ultrasonic cleaning
• Soda blasting (for full overhaul)
• Grinding & polishing
• Resurfacing
• Drilling & honing (for full overhaul)
• LIVE documentation via app

Vehicle compatibility

This overhauled engine with engine code OM642.868 fits vehicles in the series: Mercedes Benz 300, 320, 350 CDI. The OM642 was also installed in various Chrysler, Jeep, and Dodge models (e.g. Grand Cherokee, Commander). If you have any questions about your vehicle's compatibility, please contact us directly.

Variants & prices

Choose the service package that fits your situation:

• Partially overhauled / No additional service: from €6,713.00
• Partially overhauled / Removal & installation: from €11,343.00
• Partially overhauled / Vehicle collection + removal & installation: from €12,501.00

Note: This refers to the overhaul of your submitted engine. A replacement engine can be supplied on request. Prices plus statutory VAT.