Alternator AC DELCO or OEM BMW

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

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

If those are your only options you're gonna go with, Remy or ACDELCO. Keep in mind the ACDELCO is not made by ACDELCO and is just rebranded. But has a warranty and decent support.

you dont even need ISTA to figure out the alternator is dead. A fresh and charged batter will sit at 13v, used should always be around 12v. while charging it should be 13v. the fact this is dropping while the car is running suggests a shot alternator right off the bat

I always get AC Delco from RockAuto... never had one bad out of the box... Can't really speak to any other brands.

Paid $1,214 out the door. Alternator... No experience with cars and don\u2019t feel comfortable installing myself. Based off local availability, I can\u2019t imagine an option I would\u2019ve been happier with. Of course it\u2019s overpriced, but I can justify the spend based off how seamless the experience was.

I\u2019ve had an ac delco alternator from rock auto in my Honda Fit for 7 years now.

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

The issue you can run into is most common vehicle alternators are light duty at best. Lets say its a 100 amp alt, don't pull more than 40 amps continuous. A great example is the AC Delco 10si alternator. Loads of cheap knock offs and copies of that alternator all claiming crazy high amperage but none list the duty cycle. The 10si frame is designed for 40 amps of power and the heat that creates. You might be able to get a little more cooling with a better fan but you won't get 100+ amps out of one.

My 540i at 141k started eating me alive, Alternator blew up