I was on my way home today from Bowling Green and about 40 miles into my trip, the truck started to whine. It whined when ever you stepped on the gas. At idle you can hear a faint whine and as the gas increases, the whine gets louder. It kinda sounds like a supercharger. lol. So when i got back from my trip, i poped the hood and the noise is deff coming from the side of the battery (passenger side). So i got under the truck and it seems like its comin from the A/C condenser. The truck has no power lose at all and drives fine. What do you guys think by judging the videos? Is it safe to drive?

http://good-times.webshots.com/video...02940326fywkGd

 

Here's a couple of things.

First does it do it with the AC off? If not, then I might rule out the compressor. Although the pulley bearings could be bad.

I suspect the alternator or the idler pulley. Both are easier enough to check by removing the belt and having the alternator bench tested.

Course...could be the water pump, too.

Good job posting a video. It is so difficult to make educated guesses when folks just type a description. Let's hope more follow suit. Only bad thing is then smart asses like me will tell you you need this.

 

Almost sounds like a bearing to me.

 

Well i went to autozone and had the alternator load tested. No the alt is good! Thank god. lol. So it isnt the A/C compresor because it still makes the sound when i have the A/C on. So thats ruled out. So while i was at autozone buying a new coil for my dads durango (ya its missin for the 3rd time in 5,000 miles hahaha ) and while i was gettin the truck load tested i thought about the belt tensioner. So i bought one and if it is the wrong thing, ill just return it. Ill let you guys kno later tonight how it goes. Thanks again for all the help!!

 

Do you mean OFF?

 

i had the same noise once. it ended up being the idler pully.

 

Nope. The pulley rides on a bearing when the AC compressor is not on. When the clutch engages, it wouldn't make the noise anymore, if that bearing was bad.

Kinda like the "does it make the noise when you lock the hubs?" question about the needle bearings for the front axle stubs

 

well, it turns out it was the belt tensioner. Replaced that and the sound went away. Once i took the old tensioner off, i spun the wheel and it turns out the bearings bad. $40.00 dollars total. Thanks again for your guys help!

 

I've changed the tensioner and idle pulleys on my 4.6L's, like within 30K or so from brand-new. They all started squawking slightly.

Used Dayco, and their lasting...

 

Is this replacement common for the v-10s?

 

You may want to replace or relube the bearings in the other idler pulleys as well. It doesn't take long for the grease inside the bearings to dry up and be useless. The shields are removable or the bearing can be pressed out and replaced.

Replaced the tensioner pulley and idler pulley bearing in my sis's explorer. New tensioner pulley and bearing was $20 at Napa. Had a new bearing for the idler laying around a simple swap. They both lasted 160k and weren't too bad.

 

ill do that next time somthing goes bad or next time i am workin on the truck. But thanks for the tip!

 

i_eat_hybrids, can you re-post that video? I have a noise that I'm trying to figure out, and want to see what your tensioner pulley sounded like.

 

The OP's video was posted back in 2008. I clicked on the link and basically got just a blank page from that site.