I have a nitro slash 2wd and I took the bearings out of the clutch bell and the bearings are turning rough how often should I replace them and other bearings in the truck the truck is only 1 month old
There really isn't text book answer for this as it all depends on your driving style and the environment you're driving in.
You may want to think about upgrading to a bearing set from FastEddy or Boca Bearings. Also a RPM Blaster and Moo-Cleaner and Moo-Slick from @The Cow will really help extend the life of your bearings too with regular cleanings.