Take it to an oil and lube shop and have them flush the radiator.
Coolant? Bad radiator Radiator has a separate cooling tank (usually at the side or bottom of radiator) for transmission fluid. At times this tank ruptures allowing coolant to get into transmission. Most times causing a transmission failure.
check your radiator hoses and change gaskets
Be sure cooling fan for radiator is kicking in. Since radiator also cools transmission fluid. Also, be sure fluid levels are okay. Sometimes the simple things can cause the biggest problems.
The 2 lines that come from the transmission and go to the radiator are full of transmission fluid and the radiator is what cools it.
Check your transmission fluid levels. Look around for leaks...you'll see a reddish fluid around the drive axle on your transmission or around the radiator.
From the transmission? No? But antifreeze & transmission fluid can mix. Your transmission uses a small portion of the radiator as a transmission cooler, normally at the very bottom or side. In very rare instances, this cooler can develop a leak and allow transmission fluid and antifreeze to mix together. The only fix is to replace the radiator.
You replace the radiator
Fluid Connector
"transmission fluid leaking from fitting below radiator cap after replacing radiator on 99 surburban
The transmission oil cooler built into the radiator has gone bad. There is a good chance engine coolant is also getting into the transmission. This is a serious problem. Do not drive the car any further. Have it towed to a garage to replace the radiator and flush both the cooling system and the transmission. Good luck.
No. Transmission fluid lubricates the transmission. Coolant is used by the radiator to cool the engine.
Find the leak source and repair it. Usually the cause is cooler hoses.