Well first off i have a 1993 Fullsize Blazer with 5.7L 350, with a 5 speed. When i start it up it runs fine but once she warms up a little bit it develops a really High pitched and loud squeal, but the squeal goes away when i give it a little bit of gas. The noise seems to be coming from the top of the engine in one of the pully housings, a friend said that it sounded like a bad throwout bearing but then noticed it was near the top so if anyone can help me with what may be causing the problem id greatly appreciate it Thanks Greg

 

Tensioner pulley?

 

does it have ac? sometimes the bearing noise will be lower with a load. try some oil behine the ac clutch

 

IM banking on one of the accesory pully`s or bearings making the noise.My truck does the samething till I spray all the pullings and bearing ares with solcon spray.Then its quiet for a while and will start back again usualy if I go through alot of water.

 

All you have to do is pull off the belt,and spin the pulleys,if they squeak or sound rough replace it. While the belt is off start her up for a few seconds (make sure nothing is sitting on the fan) If shes still making the noise its nothing on the belt. If shes quiet,then whalla find which one is bad.