I just finished doing my rear right axle seals (inner & outer), O ring, retainer ring and bearing (inner& outer race). I purchased my parts from Amayama.com, I was impressed with the service and pricing. You also have the option of going to your local Mitsubishi dealer with the numbers that Kilbert posted, it was really pricey in Canada compared to the service and price offered to me by Amayama (delivered in six days from Japan). Partsouq is a good option but as of yet have I used them.
You will need a slide hammer/extractor kit, a small bullet style grinder (and steady hands) to cut the old retainer ring off and access to a fifty tonne shop press to put the new one on. Chances are your local garage will charge you twenty bucks to do the job of pressing the new ring on, it takes all of a minute and thirty-eight seconds (I timed the guy). There is a chance that all you will need is the inner oil seal.
I'm inclined to concur with GBNZ insofar that I actually drove for a year (periodically topping up the diff) with 80/90 seeping out onto my backing plate, yet I heard no strange noises coming from my aft end (well, not my wagon's aft end, at least
). I'd live with it for a while to see if it might be something else before tearing your axle apart. You might want to crawl under and see if there is any oil on the backing plates and if there is then see how full your differential is. Also, take a look at the inside bottom right of the driver's side door, if there is a tangerine coloured decal there with Japanese writing on it then you have a Limited Slip Differential (LSD) and will need and LSD additive along with the 80/90 oil.I find it a good policy to start simple before going deep. Many electrical issues are solved by cleaning the battery terminals and cable ends, as so many power, turbo, fuel consumption issues are fixed with a clean air filter.
Another place worthy of your perusal is the Delica FAQ section/Useful Links for Vehicle Part Identification Purposes. Take a look at the Technical Reference Libraries (L300 Dedicated Technical Reference Library/L300 Shop Manual Downloads ) while you're at it. You will find all of these in the Delica Canada Technical section on the board index. I hope this is of some use for you.
Be well,
Falco.
Good Ship 