i need the service manual fortroy built garden tractor for model 21a-128t063?

their is a question from neighbors that i should use tc2 oil for my garden tractor, is this correct.

You can find the manual online by clicking a link on this page. The manual is in pdf format and access is free.
https://www.managemyhome.com/mmh/owner_manuals/search?query=Troybilt+21a-128t063
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