You could just replace transmission filter, and drain and refill whatever you had in the pan, it's only about 1/3 or 1/4 of your total capacity.
What's the maintenance history?
I'd change fuel filter, air filter, cabin filter, braking fluid, engine oil, power steering, diff fluid.
Scan with INPA, stay on top of errors.
Look up after the cooling system.
The radiator will crack after 100k since last replacement.
Same for coolant expansion tank. Depending on your funds, I'd consider replacing all weak point in the cooling system. Thermostat, waterpump.
Best of luck!