Why its leaking transmission fluid from bottom of radiator

your transmission fluid is leaking into your radiator due to the fact that your radiator has a transmission cooler coil inside of it.
immediately replace your radiator and, your transmission filter / fluid before your engine and, transmission fail

You are leaking transmission fluid from either the fluid cooling lines that run from transmission to a separate reservoir in the radiator, or leaking from the reservoir itself. Hopefully, it's only the lines and may just need tightening to stop the leak.
There are two lines to the radiator's reservoir. One brings fluid from transmission to the reservoir, and a return line back into the transmission. Probably located on driver's side of the radiator, one will be near top of radiator, and one near the bottom. Small copper or steel lines that may also turn into rubber lines. Clean the area well with rags to locate the leak. Will probably need to have the car running to make it leak, while looking for it. You could also take a wrench and try tightening the fittings at the radiator, and tighten any rubber hose clamps that you see. If it's not the lines or hoses that are leaking, then the radiator may need to be pulled off for repairs or replacement. But 9 times out of ten, it is a leak from one of the lines.
When fixed, don't forget to check your transmission fluid level. Or keep adding till it is fixed.

Possible leaks are 1. Transmission belly Pan gasket 2. Front pump/torque converter seal. 3. Transmission fluid cooler lines 4. Axle seals at right and left half shafts.

IF TRANSMISSION LEAKING WHILE RUNNING LEAKING AT TORQUE CONVERTER SHAFT SEAL OR TRANSMISSION COOLER LINES GOING INTO RADIATOR LEAKING.YOU WILL LOSE MORE FLUID AT COOLER LINE BECAUSE TRANSMISSION UNDER PRESSURE THE OIL PUMP PUMPING IT THROUGH THE RADIATOR YOU WILL LOSE ALL YOUR FLUID QUICKLY IF LEAK COMING FROM COOLER LINES GOING INTO RADIATOR.DONT DRIVE VAN UNTIL FIX BECAUSE FLUID LOST WILL BE TRANSMISSION LOST.

Your transmission fluid runs to your cooling system to cool the transmission oil. So, in answer to your question, one of the two transmission lines (one in, bottom and one out, top) could be leaking from the cooling system.

Bring your vehicle in for a cooling system pressure check. Another thing to keep in mind when inspecting leaks is that where you see the leak may not necessarily be where the leak is from. While the leak will drip down, the wind from when you're driving will splatter the leak all over the under-carriage of your vehicle making it look like leaks are happening where they in fact, are not.

You won't go far this way. Its cheaper to tow it than replace a transmission. There are a few fluid lines to check at the transmission. Several servos and the speedometer sender are in the case.
They have gaskets and the plastic may crack. The Transmission pan can leak. The fill tube can separate from the transmission.

If the leak is coming from the inspection cover next to the engine, it can be a front seal, and if the leak is coming from where the drive-shaft slides into the transmission housing, that's a tail-shaft seal.

The fluid lines run to the front of the SUV to the Radiator where there are cooling lines going into the bottom of the Radiator. It can leak from a Radiator tank hole because there are 2 separate tanks in the Radiator. Then all you do is replace the Radiator. On some models there may be a separate Air cooled Auxiliary radiator, not to be confused with a power steering cooler.

The fluid lines will rust and need replacing. If you are trying to make a line, there are different flares for the tubing ends. Bring in your bad part to match it up.

I hope my solution is helpful to you. You need to be under the SUV to see anything. Even a quick change lube bay would make it possible to find a leak.

you have a possible leak inside the bottom tank which the fluid runs through to be cooled before it returns to the transmission.
It is like a little tank inside the bottom tank and if that leaks the fluid will mix with the water.
You will have to have the bottom tank removed to repair the problem or buy another radiator

Hi:
You are correct. Almost all automatic cars have a transmission cooler connected to the radiator with 2 hoses, near the bottom. If the hoses are leaking or not installed correctly, all of the fluid from your transmission will get pumped out on the ground, and you won't be able to move the car. Inspect the two hoses and hopefully you will find your problem.

time to rebuild your radiator. your trans cooler is leaking

Good chance it's the transmission fluid. The passenger side of the radiator is the transmission cooler side and the coolant is leaking from the transmission lines. There should be two lines, one on top which is the inlet and the bottom one which is the return line. Check to make sure there is no corrosion along the lines or that the line has not come loose at the radiator. Locate the leak and repair or replace the lines. Good luck and take care not to run low on transmission fluid, low fluid in the system will cause the transmission to burn out.