Originally Posted by elp_jc
That's just head and block. But most moving parts are made of ferrous metals. The better question would be: Is there anything a magnetic plug catches that the oil filter doesn't? My guess is probably not.
However, I was surprised not to see a magnetic plug on either the tranny or differential. The tranny has a strainer filter, but not nearly fine enough to stop metal particles. I'd be more inclined to put one there.
I put an ECS Tuning magnetic drain plug in my 2001 Golf 1.8T at about 100,000KM (60,000Miles) and the first oil-change after installing the plug I thought the engine was going because there was so much metal on it. The next oil change it had less metal on it and the third one after installing it there was hardly any metal on it.
I think that a Magnetic plug is a great thing, and obviously based on what I wrote above they do pick up metal that the filter don't catch