My 2006 Dodge Ram 1500 5.7L Hemi,has a whining sound coming from underneath the hood.Sounds as if the power steering pump is going,but the power steering fluid is ok and there is no whining when I turn the steering wheel.Had a backyard mechanic take a look and he states that its the Alternator.This whining only happens when the truck is first started and when you accelerate the gas.Any help is greatly appreciated.Thanks in advance.

 

Having any charging problems?
Starting issues?
A alt. that's on its way out will whine. But can also cause a huge voltage spike IIRC.

 

Tks dodge dude94 for the reply,but there isn't any charging issues or starting problems.The backyard mechanic that stated that it was the alternator had me place my finger on the alternator and he revved up the engine and you could actually feel the whining vibrations go through you??? IIRC??? Maybe bearings in the pulley?

 

You could also check the idler pulleys. There are a few members here that had them go, myself included.

 

Hmmm, I'm kinda tempted to run outside right now and feel my alternator to see if I can disprove (or prove) that theory. I mean since the alternator components inside are rotating they will always cause some minor vibrations, especially since that is mounted on top of the engine which is vibrating as well. I'm kinda thinking I'd be feeling vibrations on practically anything under the hood with the engine revving up. I'd try the idler pulley first, I've replaced both of mine before (one was noisy before and one just suddenly lost the bearings and ate the belt up), and I'd always try a $5-10 part first before a $100+ part. My 02 still has the original alternator on it, with 194,000+ miles.

The idler pulleys on the Rams don't seem to be a very common problem but certainly worth checking on first. FWIW my mother in law has an envoy and after doing very little research it looks like the envoy and trailblazers use the worst idler pulleys from the factory, I couldn't find a single thread on their forums where the idler pulley wasn't the cause of the loud horrible growling / moaning noise under their hoods. And two shops wanted to replace her power steering pump first

 

Take a long screw driver and put your ear at one end(handle) and touch your alternator casing with the screw end. You want to put your hand at the very end of the handle so your ear is resting on your thumb/pointer but still allowing the but end to touch your inner ear.
DO NOT rev the motor with your ear against the screw driver as it can be very loud and even rupture your ear drum! At idle, you should disticly hear the whine and it's safe for your ear. If you don't hear a loud whine but rather a soft whirling, then it's not your alternator. The high frequency whine when you rev the engine can really do damage.

BE CAREFUL of the fan. You can get your hand cut off if you get too close so just be aware of where the fan is rotating. Long screwdriver is your friend! ;-)

Just because the bearing is going, doesn't mean your alternator will have charging issue's. The whine will just get worse over time and then seize up breaking your belt and leaving you staranded.

 

DirtyDog has it. the long screwdriver trick (free) or if you like spending a few bucks auto stores sell a 'mechanics stethoscope' which has a long metal rod on the end that you use to listen to specific areas around the engine.
Certainly be careful around the moving parts of the engine.
Being stranded with a broke down truck is no fun at all and if it is indeed the pulley on the alternator going bad, by all means swap it before it's too late. But if the only testing so far was the 'finger test'... I'd get a second opinion.
Like DirtyDog said, check out a few different components to find the one with the bad whining noise.

 

Tks to all of you for this valuable info. The only cost here is to pay with great appreciation. I will try everything that was mention between all of you.Just love my Hemi. Again thanks ever so much.

 

That's why we are all here, to help, provide advice, knowledge, and talk about our good and bad experiences. Also just to help out our fellow Ram owners save money and get smarter about our trucks. Before I found this site the only thing I did was change my own engine oil.
Let us know what you find out.

 

I will certainly get back with a follow up. Again,a greatly appreciated "THANKS" to all of you.