it's been a long time since i replaced my thermostat, and that was when the top end was broken down for a rebuild. i bought a new 180 thermostat i want to install soon to finish off my new cooling upgrades, but i don't remember if i need to drain off some of my coolant or not. i know i will lose a little antifreeze, but should i drain off a few quarts to prevent from spilling alot, or is it even necessary? ( sorry if i am rambling a bit, hydrocodone )