If he's cruising in the desert and up and down the mountains, there's no stop-and-go traffic.
It's one thing that the tranny generates a lot of heat, and when you're cruising, you've enough speed to cool it down. It's another when you're in bumper to bumper traffic, and all the heat is trapped under the hood.
Those that have a tranny temp gauge have verified that cruising won't cause the temperature of the tranny to go up. It's when you get off the highway that the problem starts...
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