Squealing noise and running hot

Hi and thanks for using 2CarPros.

Based on your description, it sounds like the water wasn't circulating. First, I want you to check all belt driven accessories including the belt tensioner. Spin them and see if they turn smoothly. Next, if you reinstalled the pump already and have everything back together, check to confirm the belt is tight and not slipping on the pump. Next, start the engine and watch to confirm the pump is properly turning.

The idea that you heard the noise leads me to believe either something was locking up, which could have been the pump, or the belt tensioner has gone bad and isn't keeping the belt tight.

If you find the tensioner is bad, here are the directions for replacement. Picture 3 correlates with these directions.

DRIVE BELT TENSIONER REPLACEMENT
Drive Belt Tensioner Replacement

Removal Procedure

1. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection (L26 - 3.8L) (See: Battery Cable > Removal and Replacement)Battery Negative Cable Disconnection and Connection (LS4 - 5.3L) (See: Battery Cable > Removal and Replacement).
2. Drain the cooling system. Refer to Cooling System Draining and Filling (L26 - 3.8L GE 47716 Fill) (See: Cooling System > Removal and Replacement)Cooling System Draining and Filling (L26 - 3.8L Static Fill) (See: Cooling System > Removal and Replacement).
3. Remove the coolant recovery reservoir. Refer to Coolant Recovery Reservoir Replacement (L26 - 3.8L) (See: Coolant Reservoir > Removal and Replacement).
4. Remove the drive belt. Refer to Drive Belt Replacement (See: Drive Belt > Removal and Replacement > Drive Belt Replacement).
5. Remove the generator. Refer to Generator Replacement (L26 - 3.8L) (See: Alternator > Removal and Replacement > Generator Replacement).
6. Remove the heater hose adapters with the heater hoses from the drive belt tensioner. Refer to Heater Inlet Hose Replacement (L26 - 3.8L) (See: Heater Hose > Removal and Replacement > Heater Inlet Hose Replacement) and to Heater Outlet Hose Replacement (L26 - 3.8L) (See: Heater Hose > Removal and Replacement > Heater Outlet Hose Replacement).

7. Remove the drive belt tensioner bolts.
8. Remove the drive belt tensioner.
9. If replacing the drive belt tensioner, remove the thermostat bypass upper and lower pipe assemblies.

Installation Procedure

1. If replacing the drive belt tensioner, lubricate the thermostat bypass upper and lower pipe assembly seals with engine coolant and install the upper and lower pipe assemblies.

2. Install the drive belt tensioner.

Notice: Refer to Fastener Notice.

3. Install the drive belt tensioner bolts.

Tighten the bolts to 50 N.M (37 lb ft).

4. Install the heater hose adapters with the heater hoses to the drive belt tensioner. Refer to Heater Inlet Hose Replacement (L26 - 3.8L) (See: Heater Hose > Removal and Replacement > Heater Inlet Hose Replacement)Heater Inlet Hose Replacement (RPO LS4 - 5.3L) (See: Heater Hose > Removal and Replacement > Heater Inlet Hose Replacement) and to Heater Outlet Hose Replacement (L26 - 3.8L) (See: Heater Hose > Removal and Replacement > Heater Outlet Hose Replacement).
5. Install the generator. Refer to Generator Replacement (L26 - 3.8L) (See: Alternator > Removal and Replacement > Generator Replacement).
6. Install the drive belt. Refer to Drive Belt Replacement (See: Drive Belt > Removal and Replacement > Drive Belt Replacement).
7. Install the coolant recovery reservoir. Refer to Coolant Recovery Reservoir Replacement (L26 - 3.8L) (See: Coolant Reservoir > Removal and Replacement).
8. Fill the cooling system. Refer to )Cooling System Draining and Filling (L26 - 3.8L GE 47716 Fill) (See: Cooling System > Removal and Replacement)Cooling System Draining and Filling (L26 - 3.8L Static Fill) (See: Cooling System > Removal and Replacement).
9. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection (L26 - 3.8L) (See: Battery Cable > Removal and Replacement).

Check those things and let me know what you find.

Take care,
Joe

Welcome back.
If the temperature sensor is bad and indicates it's overheating, yes. However, you say it isn't working. When you heard the noise, it leads me to believe it is something with a bearing. Have you put the vehicle back together? If so, is it still overheating? Also, when this happened, did it seem as though it was actually overheating? For example, could you hear coolant bubbling? Was coolant flowing into the overflow at a high speed?

If the pump is good and there are no issues with any of the belt driven accessories, then things become wide open. It could be a thermostat, a plugged radiator, plugged water jackets in the engine, a radiator hose collapsing (most commonly the bottom one) and the list goes on.

Let me know if you have it back together and if it is still overheating.

Joe

Okay, then it is most likely the sensor.

Hi:
It's number 9 in the picture.

I had an afterthought. You said it was -20 degrees F. I wonder if the coolant was starting to gel in the radiator due to temperatures. When you are moving, it actually lowers the ambient temperature.

It's just a thought.

Joe