Have an engine squeal, that gets louder the lower the rpms. Its a 94 camaro with 3.4L, right around 100k on the motor. Here's what has happened up until the squeal. The oil pressure guage was bouncing around, I had this problem before and it was a bad sending unit. So I figured this might be the case again. It was doing this for about a week when the squeal started. Now for the squeal. At idle the squeal is very loud, raise the rpms and the squeal is very low. No pulleys are causing it. I know this due to taking the belt off and turning the crank pulley by hand and the squeal was still present. I raised the engine, dropped the pan and the squeal was still there. I just pulled the motor today, took the pan and oil pump off and the squeal is gone. I'm thinking of putting the oil pump back on and turning the engine by hand to see if the squeal is back. I will say that with oil pan off but not out of the way, the squeal sounded like it was coming from the back of the motor. Any ideas? I'm thinking it's a bearing, most likely a main.

 

Guess I should have added that it was 5 speed and I should have known better to look there for any issues. But I pulled 2 end main caps off, bearings are worn and so is the crank. But I went and looked in the engine compartment and noticed parts of a bearing laying in the bell housing. Pretty sure this was causing my squeal.

 

As you can see from the pics my crank and bearings were scored, so I'm installing a new crank with main and rod bearings. Wife's tired of seeing my baby sitting in front of my garage. What she just realized was half the car is sanded, once the rest of the car is done this weekend, it's getting fresh paint. But I got a new crank and bearings, I need the torque specs if anyone has them or direct me to the right post.