This was last week, but I went out to a boat we're working on and there was something missing in the engine room.
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That's the oil pan for a 1500-HP V12 Caterpillar engine. The gearbox (single reduction ratio with forward, neutral, and reverse) is in the background, and the propeller shaft is out of view on the other side of that. I assume the rest of the engine is out at the shop for overhaul. I haven't seen Caterpillars done like that, but there's a first time for everything. On a different boat years ago, there was an oil pan with a top end floating above it and empty space in between except for 4 spindly little rods holding up the top end. The 16 or so cylinders were all taken out for maintenance.
In case you were wondering, an oil change will set you back 162 gallons for the engine pictured.