Hey guys, I'm wanting to go ahead and flush the coolant since my S40 has around 66,000 miles. How do you do this?

 

not really necessarily IMO.

But

disconnect the upper and lower radiator hoses at the radiator.

Take waterhose into upper radiator (rad) neck. Flush.

for block take waterhose into upper rad hose. Flush.

Flush for just a couple minutes. Be sure to catch the old antifreeze and dispose of properly.