ACDelco Gold 335-1041 Alternator

Bought as a back up part. Tested it at an auto electric shop. They said it was a great unit and a great buy

Installed this upgraded 140 amp OEM alternator as I was replacing my aging OEM 100 amp alternator on a 1997 GMC Sierra K1500 5.7L. The install was fairly simple as the 140 amp alternator bolted right up with no issues whatsoever. I also had to replace the belt that was meant for the new 140 amp alternator. A new 4 pin harness pigtail was also required as the original 4 pin harness was a different style of shape. I de-pinned the stock harness and the new harness and removed the unused wires on the new pigtail and inserted the brown original wire(battery indicator light) into the correct pin location on the new pigtail for a perfect OEM look. Now you can buy a plug and play harness, but those are highly expensive as I personally found those a waste of time as on the original harness it has only one wire(brown) that was used with the original 4-pin harness. I also used the voltage sense wire and hooked it directly to the battery, but it's not really required, but highly recommended. I get 14.8 volts at the alternator and 14.7 volt at the battery. My alternator did come with instructions indicating what each pin does on the harness and which pen you have to use to activate the alternator. Do a little bit of research before you dive into this project as it will save you some heartache.

Fit well, works well

look good have not yet used but price was great.

I installed the AC Delco alternator but it only worked for about 6 months. I started to get extremely poor charging output from it so I had to replace it. I could not get a hold of AC Delco for their warranty, so that seemed pretty useless to even show it has a lifetime warranty. Steer clear of this one.