Alternator AC DELCO or Duralast

AC Delco makes a good product. Alternator technology is really old, so it's not difficult to do right.

I have the acdelco in my old Comanche and it works great.

I'd just get something with a warranty. I've been using Duralast from Autozone for the longest time and haven't had too many issues

Personally the AcDelco would be my top choice here with these options going new and not a reman.

Duralast Gold = new manufacture. A new unit from China. Sometimes OK, but often crap.

On rock auto I see new alternators from ac delco. Not sure about any of those brands.

We have a lady with an infinity that comes in once a year to get her duralast alternator replaced.

I bought a Duralast for my ‘99 E55 a few years ago. It didn’t work so I pulled the rectifier off of it, put it on the original one, which put out at 14.2 v back in the car. I returned the Duralast one after I made the old rectifier look like new. The shaft rotation on the Duralast felt gritty, too.

I got an ACDelco reman alternator from RockAuto, but it has a grinding feeling and bearing noise when I spin the shaft by hand. I'm not putting that "reman" alternator in the car only to have it fail a few weeks from now.

Duralast = Duramightlast. They're just overpriced cheap rebuilt cores.