What does a "K Drum Life" warning mean?

This means that one of your drums has exceeded its life cycle (carries toner from the cartridge) and generally run around $100 +/- to replace.

Yes,

That message indicates the drum is getting close to the end of life. The printer shows the message a bit before the end of life on the drum so you have time to order one before it goes out completely. You can get them from your office supply dealer or from Amazon.com

Imaging drum reach 20,000 (black only) or 5,000 (color), replace the image drum.

Supplies life
The life of the imaging drum depends on the number of black-only or color pages that print jobs
require. Imaging-drum life is also affected each time the device calibrates because calibrating causes the imaging drum to rotate. Imaging-drum life is measured in terms of number of rotations rather than number of pages printed.
The type and length of print jobs also affects drum life. A series of short print jobs uses more drum
life than an equivalent number of pages printed in a single large job. To extend drum life, print
multiple copies of a print job at one time rather than sending the same job to the device multiple times.
The life of a print cartridge depends on the amount of toner that print jobs require. When printing text at 5% coverage, black print cartridges last an average of 5,000 pages and cyan, magenta, and
yellow print cartridges last an average of 2,000 pages. High-capacity cyan, magenta, and yellow print cartridges last an average of 4,000 pages. (A typical business letter has 5% coverage.)

Is a Drum Unit problem, reach end of life, put a new Drum unit and dont forget to reset the drum after placing it in the printer.

• This message would appear if the drum unit is near the end of its life. Use the drum unit until you have a print quality problem, then replace the drum unit with a new one.
  
  
• This message would continue to appear if the drum counter was not reset when you replaced the drum.
  To reset the drum counter, follow the instructions below:
  
  
  1. Open the front cover.
  2. Press the Clear/Back key.
  3. Press 1 to reset.
  4. Close the front cover, pressing firmly on each side until they click into place.

first you are talking about the FUSER END message that means you have to change the FUSER and as for the DRUM and BELT you have to RESET the TIMER to tell the printer that it has been changed as well as for the FUSER those are consumable parts they have a life and the printer is programed to tell you to change them after so much copies.

Good luck!

Brother laser printers have both an imaging drum and a transfer belt that have a limited life span they must be replaced from time to time. Very similar to replacing your toner cartridge. purchase a drum and belt for your model and they will have installation instructions with them.

It means the drum has nearly reached the end of it's useful life, just a warning before it says it is all used up. If quality is still good you can open the front door and press the menu or options key and tell it it's a new drum and keep printing until the print quality fades.

Your printer has counter on it that keeps track of the number pages that have been printed with it. It is warning you that the drum unit is coming close to the end of it's rated life. Order a black drum unit and have it on hand. Some time in the near future the printer will stop operating until you install the new drum which will come with instructions on how to install it. If you order it now, you will avert a "Crisis" later. Ed