Hi RadLab.
I will be able to assist you with this issue. It is recommended that you perform an autogradation adjustment. Please follow the steps in the link below to perform this adjustment:
imageCLASS MF8580Cdw - Correcting the Gradation
I hope this information is helpful to you. Should you need further assistance, please contact us at 1-800-OK-CANON (1-800-652-2666).