How do I replace the drain hose on my Whirlpool top-load washer?

That has to be stated in your service and operational manual. Don't you have that?

If so : try any of the following links :

Manage my Home on-line website for on-line manuals (http://www.managemyhome.com/mmh/rails)

http://www.sears.com/Service (http://www.sears.com/shc/s/home_10153_12605)

http://www.searspartsdirect.com/partsdirecta (http://www.searspartsdirect.com/partsdirect/index.action?sid=PSHx20080114x00001I)

http://www.searspartsdirect.com/partsdirectb (http://www.searspartsdirect.com/partsdirect/index.action?sid=PSHx20080204x00001a)

My first reaction would be : replacement of the drain hose is easy to do yourself.
FIRST REMOVE the power plug from the socket, and put it on the floor before you.
Remove the back panel.
Follow the existing drain hose to locate the pump motor.
Compress the spring that firms the hose to the pump and remove the old hose and replace with new one. Make sure the spring is positioned properly again afterwards.
Close the back panel. Plug in power cord again. Check proper functioning of drain system.

Success!

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