If your transmission temperature rises only while towing, the first question is whether the transmission is operating normally under the increased load. Towing naturally creates more heat, especially on the steep grades around North Georgia, Tennessee, and North Carolina. However, excessive temperatures can also indicate an underlying issue.
Before recommending a cooler, we'd check several things:
Is the torque converter locking up properly? A converter that continues to slip creates tremendous heat.
Is the factory transmission cooler flowing properly? A partially restricted cooler or cooler line can reduce cooling capacity.
Is the engine cooling system working correctly? Many transmissions rely on the radiator to help control transmission temperature.
Are you towing within the vehicle's rated capacity? Exceeding the manufacturer's limits will generate excessive heat.
Is the transmission fluid the correct type and in good condition? Even clean-looking fluid can be the wrong specification.
If everything checks out and you're simply asking the transmission to work harder than it was originally designed for, an auxiliary transmission cooler is one of the best investments you can make. Lower operating temperatures help protect the transmission and extend the life of the fluid, seals, and internal components.