Help me with nois after shut off

Hi I have a 2002 caravan that makes a wining noise after I tern off the engine, it has been making the noise for years, I have recently perches new TC and would like to fix before I sell, any suggestions

Only thing I can think of that would possibly be is the coolaing fans ???? can you give us more info as to where your hear it and such??

Thanks for your reply, noise coming from engine compartment sounds like pulley dragging on steel or bad bearings but only for a second or tow after shutdown no noise wile running, cant pinpoint, possibly alternator?