Originally Posted by 68ss396

Your engine coolant will heat up quicker than the transmission fluid because the engine has a thermostat. The thermostat won't allow the coolant to flow until it reaches the temp of the thermostat. When it opens the coolant will flow through the radiator and the engine. The thermostat will regulate the coolant temp by opening and closing to keep the coolant at the operating temp. The transmission does not have a thermostat. Soon as the engine is started the front pump starts pumping the fluid. In the colder temps it will take longer (under normal driving conditions) to reach normal temps. And on new vehicles the transmission fluid does not run through the radiator. On trucks anyway. Don't know about small cars. The transmission has a separate cooler.