RE: Shopping.
diff oil, i run: 7 front - 10 center - 3 rear
shock oil, use a medium/heavy oil, like an 8-10, it depends on the company for the number some are 8, some 80, some 8000
i like dubro fuel filter, not heavy on the wallet, redcat has a decent filter too.
Clermontmotorsports.com carries all this and more, check him out, he's a full service hobby shop with everything you could need so if you dont see it, ask for it, just drop him an email., i get almost all of my rc stuff from him, plus real fast shipping