Brother HL-5450DN print job smears/specs

[nkqw]

Hello all,

I have a Brother HL-5450DN Laser printer which prints jobs that smear in a couple locations, and specs all over. Here's what I've tried to repair this so far.

Replacing the drum unit (same issue)
Replacing toner (it's done this for a while now).
Cleaning the slider ribbon on the current drum.

Can anyone point out what may need to be done? Here's the maintenance info, and test print (it's a scan of it).

Maintenance info

Thanks!

 

[Mitchell]

I am having the same issues with 3 Brother monochrome printers. Did you find a solutions?