Whining From Alternator

[bilesZ71]

My truck is having this whinning sound coming from the alternator. Its 2010 silverado, with less than 20,000 on it. I'm not losing any charge or having any issues just the whinning sound. It gets louder as the engine rmp rises. It did not start till one day after i went out to mud hole to pull my buddy out and ended playin in it after words. Any help would be great. Thanks.

[foghorn23]

Not questioning your diagnosis, but I had an 04 Silverado that did the same thing. It turned out to be a loud power steering pump (for which GM was/is bad) They are very close to each other on the truck and I really thought I had a bad alternator as well. As you say it just started one day.

 

However since you have less than 20K on her, let the dealer figure it out and warranty will handle it. Good luck.

[bilesZ71]

thats the thing i brought it in thinking it was the powersteering too and they said it and the truck was fine. its more just annoying than anything else. but i'll bring it to another one once i get back from deployment and see what they say. .thank you tho.

[foghorn23]

When I was having problems with my 04 the dealer I purchased from actually replaced the alternator, but of course that didn't solve anything. I actually drove about 40 miles to another dealer before I got it fixed.

 

On a separate note, I didn't realize you were deployed. I want to thank you for your service to our country and God bless you.

[Doug_Scott]

thats the thing i brought it in thinking it was the powersteering too and they said it and the truck was fine. its more just annoying than anything else. but i'll bring it to another one once i get back from deployment and see what they say. .thank you tho.

 

Take the belt off and spin the alt by hand. Can you feel anything? Should spin freely with no sticking or roughness to it. Alternators will make noise if you lose a diode as well, but will spin freely by hand. Will still charge, just not quite as good as it used to.

[bilesZ71]

no thank you for your support man, do it for yall not myself. Yeah think i'm gonna bring it to some one else to let them look. And i'll def take off the belts like you (other person) said and see if it is the alt. The only thing of buddy of mine who is a mech here in the army can think of is when i was in all that mud and water is that it splashed up and now there is s**t inside the alt. but i really do appricate yalls help with it cuz it drives me nuts when i drive it.