My brand new WorkCentre 6027 has started printing nonsense when I try to print a PDF or a JPG. I am running MacOS Mojave 10.14, but this was upgraded before I got the new printer, so nothing should have changed.
Might sound silly, Did you remove the old drivers and re-install the printer ?
This really sounds like a driver issue.
If you are printing a PDF, you could try printing as image.
Print window -> Click Advance Button -> Check "Print as image"
Just as a test to see if the job comes out 100% this time, And Vise Versa if the Check is already there (remove Check).
I don't think there is anything wrong with the printer, this is all Software / Driver.
I am using a Windows machine, so the option might be different on a MAC