Hello bdillard,
I searched our Knowledgebase, and found some things that may help you. You may need to replace your transfer unit.
If this doesn't help you may need to contact the Support Department.
The print quality from my 6280 over the course of 25 pages went from perfect to very faint text. Colors appear normal, but black is a very uniform, very light grey. The toner was fine, but I replaced it and that doesn't resolve the issue. Any assistance from someone familiar with the solution is greatly appreciated.