That doesn't sound to bad then. The chap selling tells me he had a warning light on the dash come on to tell him it wasn't working and that he had a Merc. Tech. to look at it. He put it on a computer and told him it was the transfer case leak. If I have it right all that needs doing is the fluid level topped up and then service the transfewr byt draining refilling and any filters changed. Is that correct. Sorry to be a pedant. Would driving it like this for the last 6 months have caused any further damage?