OK, an update for anyone interested. I found a great youtube video, from a guy who posted a bunch of upgrades for the TM38:
In the upgrades he lists the oil filter and filter element:
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
I am going to give them a try with some Valvoline 10w-40 motorcycle oil, lets see what happens
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