Noise Under the Hood

I have a 2005 Town and Country (3.8 v6)…In the last week a noise started in the engine compartment like a bearing going out of one of the pulleys or the Altenator going out. I have a friend who is a heavy machinery machanic…He put in a new Alt, and replaced the idler tension pully AND the other pully as well (while we had everything torn apart.) No GO. The noise is still present but seems to come and go…While accelling it is more noticable…last night driving it home when I got it over 60 to 65…it seemed to subside a bit…my friend tells me that the only thing left down there is the main crank (He replace the Powersteering pump and Water pump , and new belt within the last 4 months). He said that he noticed the crank pully “seemed” like it was a little off kilter…and stated that IF it were the main crank…That would be serious! Any thoughts??

From your initial description of the noise, I assume you are hearing a squealing sound. It is not the main crankshaft bearing. The main bearing on your crankshaft is a race bearing, which has a steady oil supply to prevent friction from destroying the bearing. If this bearing or any other rod bearing begins to fail, you will hear a distinctive knocking sound, and this would happen long before the impending failure makes your belt squeal. Also the engine would not run much longer than a few minutes with a rod knock.

It is possible your new serpentine belt is just of insufficient quality. I’d try replacing the belt again first. You may have damaged the existing belt with all these part changes as well. Do this if the noise you are hearing is a squeal, not a knock.

Take a can of WD-40 and spray a TINY bit on the belt and/or idler pulley. If the noise goes away, you need a new belt.

did wd-40 work?