Transmission fluid entering and then boiling out of radiator system. transmission i s very low on fluid ; fluid is now mixed with the antifreeze and is over flowing out of cooling system

Pam are you sure it's boiling? If the Antifreeze is boiling I'd think you'd see steam coming out of your reservoir as the water expands into the reservoir, but you didn't say you see anything like that.
Of course engines get hot, that's why we have the cooling systems but it doesn't sound like it's "boiling" to me with no signs of visible steam unless your antifreeze level is really low?

If it's really boiling, and you antifreeze level is good, then your reservoir should be getting filled up with expanded hot water that goes into it to catch it when it expands.

If the water isn't going into the reservoir, then maybe your antifreeze level in the radiator is too low and you need to add antifreeze?
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Best to fill the radiator with the engine cooled down. If you ever have to open the radiator when it's hot, NEVER open it with your bare hand as you could get scolded with boiling water. Instead use a big thick towel to remove the radiator cap off a hot engine. Again, if you can, just wait until the engine cools then open the radiator cap.

With the engine cool, you can fill the radiator with a 50/50 antifreeze mix. The 50/50 mix come premixed 50 percent water, and 50 percent antifreeze. So you can throw that stuff straight into the radiator.

Non mixed antifreeze needs to be mixed 50/50. Some people use 50 percent distilled water when they mix it because distilled water doesn't have the minerals in it that may get stuck in your radiator. That's being a bit picky about it though. Tap water works fine in a pinch. The other 50 percent is antifreeze. You can mix it right in the radiator too, put in a measured amount of the antifreeze, followed by the same measured amount of water. The water pump will mix it all together when you run the engine.

Put the cap back on and run the engine and if/when the water "boils" it should go into your reservoir. If it does boil in go in the reservoir then yes...your engine is getting hot and the antifreeze is boiling.

When the antifreeze boils, it's probably because your thermostat is stuck closed. That means the thermostat isn't letting water circulate through the radiator to get cooled. Thermostats are cheap...no more than $30 I'd say for most cars. Changing them is pretty easy too as they are usually right at the top of the engine. A mechanic may charge $100 to change it....but it's an easy job on most vehicles requiring just a couple sockets/socket wrench.

The transmission cooler has broken inside of your radiator. You will either have to replace the radiator or add a cooler. (I would replace radiator) flush cooling system and I would also do a transmission service just in case the antifreeze leaked back into the transmission while not running. NOTE:Your transmission level would be down do to it pumping into the radiator cooling system. Fill transmission to proper level running and see if it wants to work, before replacing radiator as you could have damaged the transmission by letting it run out of ATF.

Transmission cooler inside the plastic parts of the radiator may be leaking and causing the oil to mix with the coolant. GM also has a problem with their lower intake gaskets leaking, which would allow the oil and coolant to mix. Last possibility is the head gasket is leaking and mixing the oil into the coolant side but not the other way. Check your transmission fluid for mixing evidence. Another thing to do is pressure test your cooling system (Radiator, hoses ect) to see if there is a leak. Another test to try out is compression.

Remove the fan and shroud. Put a large (!) drain pan under the radiator and drain it - if you're lucky it'll have a drain petcock near the lower radiator hose. Unscrew the radiator hose clamps and disconnect the upper & lower radiator hoses. Disconnect the transmission cooler lines if they also go into the radiator (some do, some don't)... you'll want a second, small, drain pan to catch the transmission fluid.

Now unbolt the clamps that hold the radiator to the radiator support plate (across the front of the car). Lift the radiator straight up, being sure not to lose the rubber mount isolator pads. Remove it from the car.

Replacement is pretty much the reverse of disassembly - put the new radiator in place CAREFULLY so you don't damage it, put the mounting clamps back on, reconnect the transmission cooler lines and radiator hoses, check the petcock (if the new radiator has one) to be sure it's closed snugly, reattach the fan and shroud.

Now refill the cooling sytem with all NEW antifreeze/coolant and water mix, about 50/50. DO NOT reuse the old antifreeze. Take close note of exactly what brand and type of antifreeze you used, and never NEVER mix any other brand/type of antifreeze with it, only exactly the same brand/type.

After refilling the cooling system, start the car & check the transmission fluid. Top off if necessary.

No, Your radiator has many small ports which when antifreeze is mixed with oil or transmission fluid creates a chocolate milk looking mixture. This will not cool your engine as it needs resulting in overheating, and or blowing of your head gasket

On one of the tanks on the radiator you have two hosed that come from your transmission. This tank is your transmission cooler. Inside the plastic on the radiator you have a metal tube through which your transmission fluid pases through. That tube is surrounded by coolant/antifreeze which is used to cool your transmission fluid. A rupture in the tube would case fluids to mix possibly causing damage to the transmission.

YOU SUPPOSE TO USE 50/50 GREEN ANTIFREEZE AND WATER TO COOLANT SYSTEM. IF YOU USE STRAIGHT WATER IT WILL BOIL EVAPORATE AWAY WHILE ANTIFREEZE WILL RAISE BOILING POINT.

Ok well there are two issues here the boiling and the potential for the transmission to be harmed by the contamination of the tranny fluid by antifreeze. First A/T fluid is not going to harm the coolant system in the least, however antifreeze in the trans. fluid will harm the automatic transmission get the tranny flushed as soon as possible , Change out the thermostat then refill radiator using 50% water 50 % antifreeze ( premixed in container) fill radiator then run the car without radiator cap add coolant as needed, put you radiator cap on and wait 5 - 10 minutes until car comes up to operatimg temp. you must observe the engine to make sure the electric radiator fan comes on after the car runs for at least ten minutes if it does not the problem is the usually the radiator fan relay or the fan coolant temperature sensor last in rare cases the fan itself. As for the air bleed usually letting the car run with the radiator cap off for ten to fifteen minutes will do it just make sure you don't remove the radiator cap when the car is hot 2nd degree burns usually hurt.

Sounds like you have transmission fluid in the antifreeze. The transmission cooler might be leaking in the radiator. If it is, replace the radiator.

your radiator has another little radiator inside the main radiator this is called transmission cooler seems to be than the cooler has a hole or is broken the main reason for this to happend is becasue the antifreeze or coolant is not been serviced at least every 50k miles or when you mix wo diferent coolants like diferent colors they get contaminated and create acids and start corrosion in the coolant system have the radiator replaced and flush the cooling system wiht lost of water then add only the designated antifreeze on greeen coolant 50/50 mix they sell it allready mix but if you but the one is not mix mix it with 50/50 coolant and destilated water but i recomend to buy 50/50/ green coolant