From the Gates website:
''Standard fuel and oil (SAE 30R7) hose is rated for
low-pressure applications at 50 psi working
pressure up to 3/8" size, and 35 psi for sizes over
3/8". This general-purpose hose contains a light
reinforcement, and the rubber materials can be any
compound that is suitable for fuel, oil and vapors.''
Transmission fluid should be less aggressive to rubber than ethanol containing gasoline. The regular stuff should be fine for low pressure lines. Yes, you can always hunt down and pay for something better, but it would be a waste of time. Why not go all the way with stainless steel braid over Teflon?