Can't get the fan off a 2002 trailblazer

There are pulley holding tools and a wrench to loosen fan nut

Several ways to accomplish this. Leave the serpentine fan belt on the water pump pulley. Use a LARGE pair of slip joint pliers to grasp the pulley (the belt will protect the pulley from damage by the pliers) while you remove the bolts. Be sure to install a new belt, as the pliers will have damaged the old one. Alternatively, you can wrap the pulley with an old cloth rag rather than the belt. Another way to lock the pulley is to place a large screwdriver between the heads of two of the bolts, so that the pulley can not rotate. Break loose (but do not remove) the other 2 bolts. Now move the screwdriver to the two loosened bolts and use it to hold the pulley while you loosen the other two bolts. Once loose, you can easily remove the bolts while holding the pulley with your hand. Charlie

Dont hold it,i personally bang the fan clutch nut with a long chicel and hammmer.it sounds funny but works great.do it before taking belt off.