My rad fan draws enough air (roar) at cold start to spin the AC electric fans even though they are not powered up. On a D1 they should come on when AC is switched on and interior blower is on.

 

I think your right Buzz. I have the chevy heavy duty conversion for the fan clutch which is probably drawing the air through them. This would make sense because the fan clutch is locked up when cold, and not when warm.
What is the conversion to a toyota fan exactly?
Thank you!