Edited
---------- Post added at 10:11 PM ---------- Previous post was at 08:31 PM ----------
Ok so I finally gave up on it for the night. I let it run for about 30 minutes straight and it didn't overheat again, but didn't suck any coolant either. Its only got 2.5 gallons in it. Wasted a whole day on this 1 hr job and it still ain't right. I guess I'll just stick to the oil changes from now on.
Couldn't GM have avoided this problem by using a radiator cap AND the overflow jug?? Instead of creating a one-way air trap.
How did you drain it? I've never done anything on these but I would think that if you just drained the radiator then you would still have stuff in the block. Therefore, you would only need 2.5 gallons to make up for what you drained out of the radiator.
I like the idea of only one way to add coolant. I had a 99 cobra that had two ways to fill it. The bottom radiator hose came off on the interstate and I lost alot of coolant. I put it back on and filled it at the radiator. Unfortunately that was not the highest point and I overheated it a few more times trying to limp home. Needless to say, I blew the headgasket.