Xerox 6180 color laser printer - black is smearing on image side of paper. Also have a bit of smearing on the back of papaper. Was a gradual degredation, now it is really bad.

ask yourself this . Is the paper warm or hot when it has been printed on ?
check fuser unit .
No heat equals unbonded toner on paper equals smearing of toner on paper.

I expect you have to put the paper in the other side up. however if you do you could spoil the first side as it will melt the wax again when it's fusing the second side!
Good Luck.

A bit more information would be useful

This type of print quality defect shows up if you have loaded the wrong type of paper in your machine and didn't remember to change the paper type (plain paper, card stock, labels, etc.).
This can also happen if the paper has a high moisture content, or if the humidity in the room is too much. Also make sure the room temperature is within its normal operating range (not too hot, not too cold).

The problem you describe could also be caused by using non-Xerox toner/drum units. Compatible toners don't work very well in Xerox printers.

Aside from those problems, the only other thing would be if the Fuser Assembly is near the end of its life...it will also cause some print quality problems like you are describing.

hi.it could be your print cartridge.end of life.and very costly

This would normally be the cleaning unit to blame. If in doubt go,to the Xerox.com website and investigate further.
Good luck.

Your lower trays are programmed incorrectly. Change the size and or the paper type back to letter and plain paper

defective imaging unit.

Hi,

Try the link below. If the toner is leaking from the cartridge return it to shop were you got it if it is damaged.

http://www.support.xerox.com/SRVS/CGI-BIN/WEBCGI.EXE/,/?St=466,E=0000000001344030351,K=1906,Sxi=11,Case=obj(1307)


Niallbt

Appropriate cleaning procedures, as listed in the following tables, should be
performed when specific print-quality or paper transport problems occur.
All cleaning procedures are detailed in the printer’s Phaser 8400 Reference Guide or
the Phaser 8500/8550 User’s Guide.
Light Stripes or Missing Colors
Problem type Solution
Missing or light-colored
stripes on prints.
Select the automated procedure Eliminate Light Stripes from
the Control Panel.
Ink Smears, Oil Spots, or Random Ink Streaks
Problem type Solution
Ink smears on the front,
back, or edges of a page.
Select the automated procedure Remove Print Smears from
the Control Panel.
Check the maintenance kit for ink and paper-dust build-up on
the wiper blade.
Oil (drum fluid) on top edge
of print.
Select the automated procedure Remove Print Smears from
the Control Panel.

Hope this helps
pdouglasss