EXCESSIVE TRANSMISSION HEAT
Your car’s transmission operates under tremendous heat. Many of the internal
parts are referred to as “soft parts.” These soft parts inside the transmission are
made up of the rubber seals and clutches that are made of a soft friction material.
The transmission oil is cooled by a transmission oil cooler located either in, or
affixed to, the car’s radiator. Overheat the transmission and ugly things start to
happen.
The fluid (which is nothing more than a specific type of oil) reaches a boil,
cooking the transmission in its own juices, so to speak. As a result, seals harden
and there’s loss of internal hydraulic pressure. The glue on the back of the
internal clutches crystallizes, causing the clutches to weaken. Along with the
loss of internal cooling capacity, there is a loss of internal lubrication. An
increase in friction produces more heat, and the transmission fails in short order.
If you are going to tow a trailer this summer, make sure the transmission oil is
adequately cooled while towing. Normally, transmission fluid is cooled within
the transmission oil cooler located in one of the radiator tanks. During towing
the fluid gets hotter and the standard oil cooler may not release the heat fast
enough. This creates a “pressure cooker” effect within the transmission that
hardens up seals, grinds up metal parts, and toasts the clutches. So if you’re
going to tow a trailer, have an auxiliary transmission oil cooler installed on your
vehicle.