Printed copies have ghost images on them. I have never had this problem before., It looks like the image printed twice - once fine and then faint horizontal lines, sometimes some of the previously printed words, across page, maybe 5 inches below the original print (faint but very noticible.) Does something need to be cleaned or replaced?

1) try doing a full clean from within the menu on the printer, or within the computer software
2) You need to perform a half test. Put a sheet of paper on the manual feeder and do a config page from the information menu on the printer. When the back edge of the paper enters the printer, quickly open the toner door to stop the printing. Now remove the toner cartridge and look at the image below. If the defect is present, then the toner cartridge is the problem 99% of the time. There is a slight possibility that during the conditioning stage of the print process the drum of the toner is not being fully discharged so when the next stage takes places part of the previous image gets put on the toner cartridge again. Very rare. If the defect is not present then the fuser has an issue.