2003 Hemis used the 545RFE trans. But mechanically it is the same as the 45RFE trans in earlier model years. We just changed the software to allow 5th gear.
Did your friend's trans fail suddenly (no slippage at all, and then all of a sudden nothing there at all in 3rd gear)? If so, I would suspect an accumulator cover failure on the valve body. Drop the pan and look at the cover plate on the passenger side of the VB. A cover failure will be pretty obvious. Mopar sells a kit (05174633AB, $18 list) to repair this failure.