Firefox only prints a centered vertical column that has 1/3 of selected info. Margins are set @ l,r = 0.5", t,b = 0.3"
This happened after the last upgrade to Ff 4.0. The info printed is the left 1/3 column of the page, even if I highlight the whole page & "select" the highlighted portion for printing.
Opaite Mbohovái (1)
http://kb.mozillazine.org/Problems_printing_web_pages
Is that happening with all three printers??
Any chance you have a "custom" paper size selected, and not 8 1/2 x 11?
Type about:config in the URL bar and hit Enter.
If you see the warning, you can confirm that you want to access that page.
Filter = print_margin
Check the print_margin_left and print_margin_right prefs to verify that they match the settings in Page Setup. If they aren't correct, right-click each one and select Reset.