Brother MFC-8440 B - Manual (Page 182)

12 - 21 TROUBLESHOOTING AND ROUTINE MAINTENANCE
Wrinkles or creases
Make sure that paper is loaded properly.
Check the paper type and quality. (See About paper on page 2-1.)
Try printing using the straight-through output path. (See How to load
paper on page 2-5.)
Turn over the stack of paper in the tray or try rotating the paper 180° in
the input tray.
The drum unit is a consumable item and it is necessary to
replace it periodically.
Examples of poor print
quality Recommendation
B DEFGH
abc efghijk
A C D
b c d e
1 3 4