Whirring noise after alternator change

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OR VietVet

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You gotta remember that all CarQuest alternators are not built/remaned by the same company. More than one rebuild/build company is doing them. Way too many percentages against that.

Just like GM does not make all the components that are put together to make a Tahoe or Yukon. Many suppliers make parts and put the GM logo on them and therefore GM takes control and responsibility for that part/component.
 
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Joseph Garcia

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Check Rock Auto for the tensioner assembly, as they have good quality parts, most likely an OEM option, and a fair price. As stated above, purchase the entire tensioner assembly, so that you get new bearings and a new tensioner spring.

I made this replacement a few months ago (not for whirring noise, but for a broken spring in the tensioner), and it is an easy job to perform.
 

TheAutumnWind

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Check Rock Auto for the tensioner assembly, as they have good quality parts, most likely an OEM option, and a fair price. As stated above, purchase the entire tensioner assembly, so that you get new bearings and a new tensioner spring.

I made this replacement a few months ago (not for whirring noise, but for a broken spring in the tensioner), and it is an easy job to perform.
That would likely fix it... though I would try getting a stethoscope and determining what the actual problem is before throwing more and more parts at it.
 

dacula789

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I have developed a whirring noise after replacing my alternator in my 09 Tahoe LTZ. It goes away in neutral and park, and after acceleration, but gets a bit louder when a load is placed on the electrical system(lights, heater, a/c) when in drive or reverse and brake on(idling at stop sign with foot on brake). Is there a noise filter or some other electric component I may have blown when changing the alternator; I followed all the precautions like disconnecting the battery neg terminal. The belt is like new and I’ve changed the alternator twice with the same remanufactured model from Advance Auto. The noise was not there with the original alternator which I replaced because it was overcharging.
I had the same thing happen when I replaced my alternator. The noise eventually subsided. Mine sounded like a turbine engine spooling up and down with the rpms.
 

dougo

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i had the same thing new alternator change the tensioner drove me nuts tried old belts that i had as spares ( i change belts every 50K just because i can) same noise put on a new ac delco belt and the noise is gone (The old belt had less them 50K on it Not ac delco)
My new alternator was a carquest as well but the noise started before i changed the alternator so i am reasonable sure it was the belt all along
 
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Blk 09 LTZ

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Well I got a new idler as the low cost starting point, and the noise actually became a little more pronounced. So listened intently again, all around that side of the engine, and now it sounded more like it was coming from the steering pump just below the alternator. Turned the steering wheel with the engine running and the noise changed pitch up and down!

So did I mess something up in the steering pump when I took the belt off to change the alternator? And is there a fix without replacing the pump? You know that feeling you get when you feel like an idiot?
 

wjburken

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Well I got a new idler as the low cost starting point, and the noise actually became a little more pronounced. So listened intently again, all around that side of the engine, and now it sounded more like it was coming from the steering pump just below the alternator. Turned the steering wheel with the engine running and the noise changed pitch up and down!

So did I mess something up in the steering pump when I took the belt off to change the alternator? And is there a fix without replacing the pump? You know that feeling you get when you feel like an idiot?


It would be rather unusual for someone to damage the power steering pump removing a belt, but stranger things have happened.

As far as feeling like an idiot, well, get over it. We have all been there at one time or another. This has been a learning experience for you so just chalk it up as a teachable moment.

That being said, before you jump in and start replacing the power steering pump or parts of it, get a mechanic’s stethoscope and make sure that that is where the sound is coming from.
 

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The PS pump will probably get a little noisier anyway when the wheel is turned and the truck is sitting still. It has to work harder to turn the wheels side to side when they're not rotating forward or backward.
 
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Blk 09 LTZ

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It’s been a while since I visited here, due to a family emergency. But the power steering pump is definitely where the whining is coming from per my mechanic. He said he has the same 2009 Tahoe as mine and his has whined for years with no steering problems. He also said it’s a 2 1/2 hour job to replace the pump because you have to practically take the whole front of the truck apart, and I may as well replace the lines too. I only put about 500 miles a month on the truck, only using it to tow and haul occasionally. It’s been whining about 3 months. My questions are, how long can I expect the whining pump to last, and is there a less expensive remedy to replacing the pump?
 

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