Screeching noise from engine-most likely cause?

[shayk]

Looking for input of the most likely cause of the screeching noise coming from the front of my engine.
I can hear it, but cant pinpoint the location.
2003 4Runner, V8 with 222K
It isn't a squealing belt, more like a bad bearing screech. Its been ongoing for about a month, hasn't changed much, nothing has grenade yet either.
Matches engine speed. Happens in Park
Replaced the timing belt and water pump at 130K with aftermarket, not oem parts.
I seem to be loosing coolant because the overflow tank goes empty, and I can sometimes smell coolant, but I never see any, no leaks visible under the truck.
Wondering if the bearing seal on the waterpump might be bad, leaking coolant into the bearing?

If I have time this weekend I might pull the belt off and see if anything feels wrong spinning by hand.

 

[RUN-4-LIFE]

My first guess would be belt tensioner pulley.

 

[Brian3676]

If its the water pump there should be coolant coming out the weep hole usually. Sounds like you're about due for another T belt job anyway though, so just go in a do it all. The Asin kit off Amazon is like $220 if I remember correctly. All OEM parts without the OEM badge/price.

 

[bergs]

Guessing plastic pulley contacting the rubber belt is what's making the noise. I know mine sounds horrible for at least the first 30min of driving.

Loss of coolant might be related to the radiator seams failing . Consider inspecting the radiator for signs of leakage.

 

[aude311]

Looking for input of the most likely cause of the screeching noise coming from the front of my engine.
I can hear it, but cant pinpoint the location.
2003 4Runner, V8 with 222K
It isn't a squealing belt, more like a bad bearing screech. Its been ongoing for about a month, hasn't changed much, nothing has grenade yet either.
Matches engine speed. Happens in Park
Replaced the timing belt and water pump at 130K with aftermarket, not oem parts.
I seem to be loosing coolant because the overflow tank goes empty, and I can sometimes smell coolant, but I never see any, no leaks visible under the truck.
Wondering if the bearing seal on the waterpump might be bad, leaking coolant into the bearing?

If I have time this weekend I might pull the belt off and see if anything feels wrong spinning by hand.

put cardboard under your car when you park it for a hew hours.
are you adding distilled water to the res? also when you check your radiator is it full or do you see air where the cap goes?

could easily be a pully or the water pump.
if you can get your hands on the tensioners you can try moving them off there axel's if they move at all thats your bad bearing

 

[BOFFROAD]

Looking for input of the most likely cause of the screeching noise coming from the front of my engine.
I can hear it, but cant pinpoint the location.
2003 4Runner, V8 with 222K
It isn't a squealing belt, more like a bad bearing screech. Its been ongoing for about a month, hasn't changed much, nothing has grenade yet either.
Matches engine speed. Happens in Park
Replaced the timing belt and water pump at 130K with aftermarket, not oem parts.
I seem to be loosing coolant because the overflow tank goes empty, and I can sometimes smell coolant, but I never see any, no leaks visible under the truck.
Wondering if the bearing seal on the waterpump might be bad, leaking coolant into the bearing?

If I have time this weekend I might pull the belt off and see if anything feels wrong spinning by hand.

I am having the same two problems, squeaking sound and empty coolant reservoir. I don't think they are related to each other in my case. I know Im loosing coolant due to a hole in the overflow hose. Pull your hose out from the plastic piece its tucked under and check the bottom for a leak. Mine looks like it has been rubbing on the plastic over the years and has eventually worn through. My squealing I believe is the power steering pulley needing replacement.

 

[luke87gt]

It's almost certainly an accessory/pulley on the front of the engine.

Just have to investigate. You could take off the belt and rotate everything by hand to isolate it. Some people will take a 4ft length of garden hose and bring it up to their ear to pinpoint where it's coming from.

Look closely at the water pump, tensioner pulley, idler pulley, alternator pulley, AC pulley, and PS pulley.

 

[shayk]

If its the water pump there should be coolant coming out the weep hole usually. Sounds like you're about due for another T belt job anyway though, so just go in a do it all. The Asin kit off Amazon is like $220 if I remember correctly. All OEM parts without the OEM badge/price.

Trying to put off another T-belt change. Currently looking for a 5th gen, so I may be trading it in.