I was reading the Nissan manual and noticed the following:

If fluid is very dark or smells burned, refer to AT section for
checking operation of A/T. Flush cooling system after repair of
A/T.
I If A/T fluid contains frictional material (clutches, bands, etc.),
replace radiator and flush cooler line using cleaning solvent
and compressed air after repair of A/T. Refer to LC-17, “Radiator”.


Now, my question is how is the coolant(antifreeze) connected with A/T Fluid directly? I always figured the A/T fluid runs in a different compartment in the radiator? Can anyone care to explain how this works?

 

Your AT oil goes through the rad (there is a mini cooler in it) but it is insulated, i.e. does not mix with coolant, it uses the rad to cool it... So if you see some water or AT oil discoloration (going black or white) that could mean that the mini-cooler in rad may have cracked and coolant is entering the oil and going to tranny, hence the recommendation to replace the rad, flush the coolant (as some tranny oil may have gone in) and tranny... Hope this helps...