Originally posted by fly5150
I would say if you need to add to your radiator, then you must do it while it is cold. If you take the radiator cap off when hot, its under pressure and could burn you. Do you have your coolant overflow tank? if so, then just make sure that is at the full mark when hot, if its low, fill that while hot.
You are correct, I was doing some research on this and found this link
coolant level check
I know to open the radiator cap slowly to avoid being burned, but it says adding cool coolant to a hot radiator could cause it to crack. I should have known this:doh: