My mid 2009 13" MacBook Pro says service battery in the battery drop down menu thing in the top right of the screen. It says I can continue using the MacBook but I should get it checked. The back of my MacBook gets quite hot when using it and the battery life has gone down to just 2-3 hours on a charge. I won't be able to go an Apple store anytime soon so is there anything I can do by opening up the MacBook and tinkering around with things? I'm fairly technically proficient so I'm comfortable with opening up the MacBook and doing strange stuff to it.