Thats when it starts to creep. I mean I can drive it longer than 5 before it creeps at all. Heck, i can maybe cruise around for 15 and only then if i get on it, it begins the cycle of up and down temps

If your temp gauge is going up and down, that indicates to me you have air in the system. I don't know how that car is set up. But on the 3800 you can add coolant in to the hole where the thermostat goes until it'* full, the slowly put the thermostat in making sure you don't trap any air. Bolt it up and then fill the radiator threw the fill cap until it'* full. Start the engine with the cap off. Let it heat up and watch for coolant flow. Putting the front wheels on ramps also helps because that makes the front of the engine the highest point. The heater core is a good place for air to hide.

If it climbs when you get on it then comes down when you let off it sounds like a head gasket. Any coolant in the oil ?

Pressure-testing can be free if you rent from an auto parts store a coolant pressurizing pump and then return it. They give you all your money back, or you can just buy it and keep it. If you're going to spend $70 on a pressure test, you could spend ~$75 on a pump and do it yourself, then keep it or get your money back. I'm not sure about what a pressure test can do for an air bubble, but you could also look into methods of bleeding the coolant system in your car. Good luck!

I am guessing they are hunting for a pin leak somewhere. They are going to do other diagnostics (*im sure at my charge), ie, check the fans.

Waiting to hear from them now.

Update. The dealer gave me a call and said pressure testing the system came up with no bad results ($70). Further testing showed that one of two rad fans isn't turning on. They are now trying to figure out why. Electrical gremlin. Dealer told me to be ready for a 5-700 dollar bill.

oh god, good luck

Another update. Apparently some module under the fuse box in the engine bay is the culprit. $300 part, $350 labor, back order 4-8 days.

We don't call them steelerships for nothing.

dont you think its something you can do yourself?
parts are always cheaper online and prolly takes a week to get here and labour is your time