Rep Power: 680

I just got a new radiator for my car (6 months old) and its making a loud, whispering type noise. Like a spe-spe mixed with a che-che. When I sprayed some WD40 lube on the belt, it stopped. Could it be a bad pulley like my ac-pulley, it stopped working after two months of use and I dont want to waste money refilling freon if the ac might be bad. Also, the belt, belt tensioner, water pump, and alternator are all new.

 
Rep Power: 1121

replace the belt now that you sprayed wd 40 on it and ruined it (they don't like oils it breaks down the belts inside) a bad pulley can do that as can something rubbing

 
Rep Power: 778

As arch said, you'll need to replace that belt. If you ever need to lubricate a belt, use silicone belt dressing. (Not the spray cans, those are about worthless)

Again, as arch said, it could be a bad pulley, tensioner, or bad bearing. Hard to tell without hearing the nose you're speaking of.

 
Rep Power: 656

is the belts tooths kinda getting old/cracking or look worn if so it is just the belt going old and bad... just change it... it only takes about 10 minutes tops

 
Rep Power: 680

I did replace the belt back in Sept, both the old and new belts whispered. It randomly stopped but is too loud whenever I initially start it.

 
Rep Power: 778

Just when you start it?

Sounds like a belt tensioner. Luckily they are cheap and easy to install (takes about 2 minutes on a 3.8).

If you replace the tensioner, replace the belt as well imo.