How to replace main engine seals oil leak in a 2001 Honda Odyssey,how much and is there a step to step info or video to help do it yourself

SOURCE: Rear Main Seal Leaking

Hello, it's not "easy" but, it's doable.
You'll need to follow the instructions and don't take shortcuts. ask for help if you need it.
Use this link to get an idea of what is involved. Ignore the "remove transmission" part. It can be done without removing the tranny. If you decide to do this buy a service manual to help you. If you have any questions feel free to ask.
Here is the link:
http://www.autozone.com/shopping/repairGuide.htm?pageId=0900c152801caf2a

SOURCE: Replacing the timing belt on a 2002 Honda Odyssey

you need a haynes repair manual . it save you time. it shows you step by step . what to remove to get to timing belt or chain . show you photos how to set timing chain cam and crank timing marks.

SOURCE: 2001 Silverado 1500 Z71 4x4 oil leak

i had the same problem and it turned out to be the gasket on the rear main seal housing not the rear main seal.

SOURCE: Honda odyssey 2005

The tranny fluid on most cars and trucks is 30,000 miles ,as far as the engine oil if you use a good oil brand like Honda motor oil or even like Motorcraft they are a synthectic blend 5w20 and you can go 5,000 miles between oil changes.Now if your useing regular motor oil change it every 3,000 miles.Hope that helps

SOURCE: 2001 Honda - New Catalytics & O2 sensors -- new 0420/1739/1456

I would send the car for a smoke test for the emissions leak...Find out where the leak is comming from..Repair it..Reset the codes, then do a drive cycle and see what happens...