Impala Forums banner

1 - 5 of 5 Posts

·
Registered
Joined
·
598 Posts
Discussion Starter · #1 ·
Hey guys, I think my alternator bearing is going out on me, and I'm trying to order a new alternator. It seems there are two alternators that fit in my car, which has the 3.9 AFM LZG engine. Every part site I've been to lists two alternators... RockAuto, AutoZone, GMParts... etc, etc.

There's a 125amp Bosch, and a 150amp Denso. I can't figure out what the stock alternator amperage is for the life of me, so I was hoping someone could provide some insight. It's an 08 LTZ btw.

Also, let's say for example that the stock alternator is 125amp. What happens if I throw in a 150amp alternator anyway? From my very basic understanding of electronics, components draw only the amount of power they need to run, so installing a 150amp alternator really shouldn't mess up my electrical system. Is that correct?

Thanks in advance!
 

·
Registered
Joined
·
765 Posts
150 amp alternator would ideally be better.
Shouldnt cause any issues, alternator upgrade is a pretty common thing in the car audio world.
 

·
Registered
Joined
·
1,315 Posts
call rock auto and ask but i imagine it will work just fine. i'd go with the larger output because, well...why not? might add an accessory or amp later on that you would need the extra overhead for. maybe the 150 is for "police application" but i imagine the belt routing is all the same. should be the same plugs and everything. rock auto should have that info though.
 

·
Registered
Joined
·
598 Posts
Discussion Starter · #4 ·
Thanks for the responses, guys. If I were to change it out to 150amp, I'd have to change out the main fuse from 125 to 150 as well, right?
 

·
Registered
Joined
·
588 Posts
I am not 100% sure about what was offered to why there was 2 but even back in the 00-05 they had 2 as well.... About changing out a Fuse there is no fuse for you to change out. What may be an issue is the Size of wire from the Alt to the Battery. However I don't think that is going to be much of an issue for the Impala as it should be under 5 feet from the Alt to the Battery and the cable for both 125 and 150amp alt should be 4AWG already... If you were going to go over 150amp then you for sure would need to go with 2AWG however in all honesty upto 190 4AWG is fine...

If you are running a large sound system and going to draw loads of power from your cars Alt. I would upgrade to a good 2AWG to be safe....

Edit: Also forgot to say that only other thing that it could be a pully or something that may making the change to the Higher output a little harder... In some cases you have to use your own pully anyway.. So I am not 100% sure why the 2 or what was so much bigger for draw for there to be 2. IF the pully is the same and no issue I would go with the HO Alt just to make sure I had the extra power if needed.

James
 
1 - 5 of 5 Posts
Top