New alternator whining/supercharger noise.

[94 Silverado]

I bought a NEW Duralast Gold 105A alternator to replace the factory one that had 167k miles and started squeaking. The new one seems to have a whine to it. It's not crazy loud but I notice it at idle and deceleration. Is this normal for these trucks or did I get a bad part?

 

[Madscientist]

I have noticed this with new alternators. It seams to go away in about 1000 miles.

 

[Busted Knuckle]

I may have the same alt. Whine after startup to replenish the battery drain and then is quiet. If its charging OK I wouldn't worry. Decel whine is unusual and I'd suspect something else. I've got new whines after replacing the transmission mount. Nothing is wrong.

 

[Erik the Awful]

I have noticed this with new alternators. It seams to go away in about 1000 miles.

I've put four alternators in my Mustang. The cheap ones were quiet, but crapped out after a year. The expensive ones whined, but lasted two years. I think it's all made by the lowest bidder in Bangladesh, boxed in China, and labeled in California.

 

[tsr2185]

I bought a NEW Duralast Gold 105A alternator to replace the factory one that had 167k miles and started squeaking. The new one seems to have a whine to it. It's not crazy loud but I notice it at idle and deceleration. Is this normal for these trucks or did I get a bad part?

I just got the same alt and have the same whine. Any problems since then with it?

 

[Zseventy-one]

I have a new powermaster 130 amp and it whines. I had to take mine apart to "clock" it for it would bolt up so thought I might of damaged it somehow...
Guess a small whine is normal depending on the set up?

 

[Dropped88]

First mistake was using auto zone parts. I have the unfortunate job of install their parts at work and the failure rate is ridiculous its not uncommon to have to do the same job 3 or 4 times.

I actually replace a 6 month old auto zone alt today for overcharging at 20v boiling the battery to the point it was dripping below the truck

And we have a Nissan murano that I know is working on its 4th or 5th AZ alternator in less then a year. But hey management gets a nice kick off the AZ parts they sale so it is what it is

Sorry about rant been one of those days

 

[someotherguy]

First mistake was using auto zone parts. I have the unfortunate job of install their parts at work and the failure rate is ridiculous its not uncommon to have to do the same job 3 or 4 times.

I actually replace a 6 month old auto zone alt today for overcharging at 20v boiling the battery to the point it was dripping below the truck

And we have a Nissan murano that I know is working on its 4th or 5th AZ alternator in less then a year. But hey management gets a nice kick off the AZ parts they sale so it is what it is

Sorry about rant been one of those days

Duralast must be an OEM supplier for Ford the 2020 F450 work truck I drive has only 24K miles on it and it's boiling the batteries. Just told the bossman he needs to get it checked out. They're wet on top, corroding the crap out of the terminal ends, and stinking like a whole crate of rotten eggs..

Richard

 

[skylark]

Unfortunately all parts are crap. Few are better than others. That said, Autozone is what Taco Bell is to Mexican food. Yeah you can eat it but there are better options.

 

[Zseventy-one]

I have a new powermaster 130 amp and it whines. I had to take mine apart to "clock" it for it would bolt up so thought I might of damaged it somehow...
Guess a small whine is normal depending on the set up?

It is actually this one which is a 140 amp https://www.summitracing.com/parts/pwm-57861

When the alt died on my 03 rustang, I replaced it with an expensive (at the time) $300 PA Performance that lasted a month before failing. Had to return it to PA performance on my dime for them to fix it, said that a diode went bad or some crap. In it's defense I was running under drive pulleys but no aftermarket electronics, stereo etc.
Neither the failed alt or the repaired alt or even the stock alt whined. This one has whined out of the box, so who knows.