Call Freightliner or look for a tag on the alternator, which might be hard to do on a rear radiator setup. I'm pretty sure that's the only thing they used on the XC chassis in 2004 and following years.
Leece-Neville makes lots of heavy duty alternators for trucks, busses, and diesel RVs. There's nothing wrong with the brand. It's just that the particular alternatror that FL went to in the 2004 model year had a batch that burned up prematurely. I believe that any replacements are of a different spec number and you shouldn't have any problems.
Mark & Leann Quasius
2016 Cornerstone 45A
2007 Allegro Bus 42QRP (Sold)
2012 Jeep Wrangler Unlimited - Rubicon