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Carl G
2025-08-07 18:45:21
I read some reviews where there were complaints of the alternator making a whining noise. This may be normal for new alternators until the brushes are seated. The alternator I installed made a slight whining noise but after 4,000 miles since installing it, I no longer hear it. The original alternator has 225,000 miles on it and was still working but as a "playing it safe" I decided to replace it because I didn't want to break down on a deserted highway somewhere between here and there.
Jeff M.
2025-07-30 15:53:37
Straight drop in for my 2005 Duramax diesel. Immediately was charging at 14.4 volts. Keep in mind there are bushings that the mounting bolts go through and they will most likely need to be pushed back out to make room for the new alternator to drop right in. If you go to drop in your new alternator and it appears too tight or won't fit in - DO NOT HAMMER IT OR FILE DOWN THE ALTERNATOR... just make a little press. Take a look at my pictures above, I just used a long spare bolt & nut and found a socket large enough to fit over the outside of the bushing but small enough to rest on the mounting cradle. I then pushed the bolt though the socket and attached the nut on the other end (see pics). I then took an open ended wrench on each end and tightened the bolt until the bushing moved forward and was flush with the mounting cradle. There are only two bushings and they are both up front. After this the alternator dropped right in and I bolted it up. When you tighten the bolts on the new alternator, the bushings will move forward and fit snug on the new alternator making a tight and aligned fit. I hope this helps!
Customer
2025-06-27 10:23:27
Great packaging, easy install
KEITH FRANK BLANKENBILLER
2025-06-12 10:37:27
It fit and worked like a factory built should. The price was also reasonable . The local parts store had (brand new also) at a higher price. 5 stars!!
Clippers
2025-06-05 18:01:00
This alternator worked well while it lasted, but 2 years and 5 months after it was installed it failed. It only output 11v, constantly killed the battery and left me stranded on the side of the road. I was expecting at least 5 years out of this since it is a GM ACDelco alternator. The original alternator it replaced lasted for 18 years. I guess when they build the cars they use better parts. Funny that it failed right after the 2 year GM warranty. I decided to buy an Autozone Duralast alternator that has a lifetime replacement warranty if it ever fails. I also opted for the 145Amp. The original and this one is a 105AMP.
Jeffrey moore
2025-05-21 18:58:22
Product was as said works great thanks
H. Thorp
2025-05-04 13:44:07
For the price, you really can't beat this. I bought this for my '03 Chevy Silverado 2500HD w/ 6L (LQ4), which it fit as expected. Removal/install took me about 15 minutes, not including replacing the pulley (see below).Pros:Seems well built. Brand new-not a poorly re-manufactured unit like most other units at and above this price. Easily installed on the LQ4's accessory drive.Cons:Pulley was damaged upon arrival (one of the ridges was nicked, and unfortunately there was a slight bulge into one of the grooves, which would likely damage the serpentine belt) . Not wanting to go several more days without a working alternator, I decided to swap the pulley from my old alternator onto this unit instead of returning it. Given the price, I really can't complain too much on this issue. Alternator is assembled in Mexico. That's better than Made in China, but made in USA is always preferred if possible!Other thoughts:For those of you replacing one of these on the GM 6.0L truck engine, the following may prove helpful: You will likely need to pry the old one out. Just stick a prybar under the old alternator and pry it upward. (after removing the serpentine belt, of course!) Once you've worked it out, I found that it's easier to get the new one in if you take a hammer and gently work the little sleeves in the front holes of the mount towards the front of the truck (you just need a millimeter or so of movement. They'll snug back up to their original position when you install the new alternator). If you don't push these forward, the new alternator can be very hard to reinstall. (Of course, I'm not responsible if you break the mount or damage anything else while doing this!) Hopefully this helps someone.
Chelsea
2025-04-19 15:33:21
2 bolts electric pigtail and tiny ground. Didn’t take 10 minutes to install and reconnect. Took longer to get the serpentine belt back on and centered. Local repair shop quoted $815 for re-manufactured 73 year old did it myself $150 saving $665!!! Party at my house
Sharon W.
2025-04-18 15:32:34
works great, 3 years old still good
joel trandafir
2025-02-05 15:25:32
Installed the alternator and fit perfectly as advertised I’m very happy with
ian arthur price
2025-01-29 14:22:06
Works as new not reman alternater should Good value
The Count
2025-01-12 14:59:57
As expected from ACDelco, this is a well made unit that fit exactly as a GMC replacement part. The wiring receptacle / connector was also an exact fit that meant it only had to be plugged into this new unit.The issue during removal of the original unit was that the two long bolts that hold the alternator in place had corroded on the far end hidden tips and they did not want to pull through the body of the alternator / engine mount. Spinning those bolts with a air gun for a minute removed the crud that was blocking their removal and they came out then with only using my fingers.As the engine mount tends to be very tight, it took some effort to spread its arms and slide and tap the alternator fully into place. Don't file it down as is suggested on websites.There were not any issues relating to the manufacture or sizing of the replacement alternator.I recommend this alternator.
Erv
2024-12-22 17:32:29
2001 Silverado, 5.3L. Fits perfect, quiet, and puts out 14.5 Volts. Driven with it about 200 miles, works like the original did. Good buy!5/28/2023 - Update - Well I though the alternator was great, seems about a week ago whenever using signals, windows, brakes, almost any electical accessory, my voltmeter now bounces up and down in my guage cluster. I have load tested the battery, and checked voltage, which is bouncing up and down a few volts. I have check all grounds and bulbs, which are all good. Never had this with any other alternator. HMMMM maybe I should have bought at the local parts store, then I could get an exchange. Not even 6 months old.....not to impressed!
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