fluid leak

I have a 2008 Honda Element and I bought it with 56K miles. I now have 89K miles and I am just starting to notice slippage from first to second gear. I checked the trans. fluid and it was low, don't know why. Could it be leaking? Is this a problem with Honda Elements. I bought it for the...

My rear differential is leaking. I beleieve are the axle seals, have any one replaced theirs ? Are they difficult to do, or it is a dealer job ? I will like to hear from others with same problem.