Personally I think you are worrying over nothing.
Next you will be chasing answers as to why the engine
oil goes black so fast.
I have done 12000kls now and not changed the fluid, it is darker than the brake fluid (But I used a dark green colored fluid), it still operates perfectly well.
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Cruising in 5th
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Never be afraid to do something new, Remember, Amateurs built the Ark: Professionals built the Titanic.