Has anyone seen or heard of a car battery with a overflow tube before? I've never did. Just had my battery exchanged and this one has it. It's about 5 1/2 inch long rubber tube connected between the terminals. Would it spill out easily? Went on line and found some did.

 

I've seen them but they are not super common. Mount the battery tightly and make sure it is not overfilled and you should be fine

 

All of the P2 cars are supposed to have them. P2= S80,S60 2001 and up V70 and XC90.