I have seen collant system stop-leak plug up heater cores and thermostats, and even a radiator plug up when used on neglected systems. I'd stay away from ay stop leak products. kind of like putting a bandaid on a broken leg.

 

I'd agree and advise use of the bars leak product only. Not as a repair but as a better than nothing. If needed drive HHR now, cuz it's too darn cold to fix now solution.
In case of the 2005 Dodge it was a smallest pin hole under pressure and a small quantity sealed it.
I used an excessive amount and conditioner and new antifreeze when I replaced water pump and related parts on my '99 Astro 4.3L. Has rear aux heater.
Have had no troubles with blockages or overheat. 60k ago now.
Some sealer has come up into radiator cap area but easy to clean away.

 

Thank You Each again for helping.
Today I drove it 3 miles, then it cooled for an hour, then 3 more miles. No leak was found when hot. An hour or so later, no leak.
Next, I drive it about 30 miles total. No leaks showed when hot or after it cooled off.

Do leaks seal themselves or was today just a luck day and I should consider that it is leaking?

Paul

 

If the level is good relax.

 

The level under the pressure cap, not the recovery tank. OP hasn't confirmed that they are checking under the pressure cap

 

Was this the first drive after some of the extraordinarily cold weather we recently experienced? If the coolant slushed up, it would restrict the flow, causing local boiling, in turn releasing excessive coolant into the recovery tank, possibly overtopping it. Any chance the car was left running in that spot to warm up?

So yeah, it could be a one time event, if it doesn’t get that cold again.

How sure are you that the flush/fill procedure fully drained the system? You could have less than 50/50 in there.

You should definitely check the coolant concentration and replace the thermostat with the correct OEM item. I’m not a fan of “flushing,” especially when changing coolant regularly. Just dump, being sure to remove the plug at the water pump, and refill. GM recommends 60/40 mix for colder climates. I prefer that, precisely because of events like our recent “arctic blast.”

PSA, leaks are 1000% more likely to get worse than to “seal themselves.”

 

Thanks Again All for helping.
It was mentioned that the overflow tank could have overflowed out of the tank. The overflow tank is on the opposite side of the radiator from where I saw coolant.

The level in the overflow tank hasn't changed. The level under the cap (cold) shows a full hose. I dried around the hose at the bottom of the tank where the coolant was leaking. I've also checked above that hose area where the transmission lines connect to the radiator tank. They never got wet. Only at the bottom of the hose and below where it dripped onto a bracket.
Since then, I've driven many miles and checked it hot and cold. Running and off. No leaks show.

So, I'll do as Don Brew suggested and relax! (But keep an eye on it for some time to come.) Perhaps I got lucky!

 

Forgot to mention the possibility that someone was parking in your spot in your absence set up a cam.