Please TRY to research the forum for answers already posted. I think this is the RD time posted an answer to this same question in as many days.
Yes, K&N works fine, it's just less inexpensive as other alternatives.
filter oil is available at most hobby shops, auto parts store, motorsports retailer, napa, pep boys, advance, auto-zone, a and a, or walmart around. Despite this, some still want to use a substitute in which case, good ol plain jane straight 30wt motor oil will also suffice.
Rolex, Woodie, RobMob, RC Addict and others, hats off to ya! From all of us, thank you for your patience, persistence and ongoing support and wealth of information to us all.......no matter how many times we ask it.......or don't

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