Visual alternator differences

jliddle

New member
Jun 30, 2012
331
0
0
NC
I had a previous truck with a pretty large stereo system in it, of which I kept the alternator for a spare. It is chrome plated which leaves me to believe it may be aftermarket and possibly a bigger amperage than factory. I don't see any markings on it. Does anyone know of a way to tell if it is infact a bigger one?



 

THEFERMANATOR

LEGALLY INSANE
Feb 16, 2009
3,890
44
48
44
ZEPHYRHILLS, FL
It's an AD244, but as to the size only way to know is to have it checked like posted above. Also with the AD244, you have to get them HOT to know true output. They rate the amperage at something like 250 degrees, at 100 degrees a 145 amp unit can put out 200 amps from what I read.
 

c20elephant

C20ELEPHANT
Apr 25, 2013
2,065
0
0
Phoenix, Arizona
Or just use what the factory designed to work with, and use quality GM part's ;).

The factory alternator is bare minimum, even a 200amp upgrade new alternator from the 145 stock is an improvement over the stock design with no modifications necessary, plug and play. I can purchase one locally for around $200.00....
 
Last edited:

DAVe3283

Heavy & Slow
Sep 3, 2009
3,733
305
83
Boise, ID, USA
I wouldn't call the factory bare minimum, there are plenty of trucks on this site with a ton of electrical upgrades still on the stock alternator
Exactly, I ran the stock alternator for over 100,000 miles running an electric air compressor, electric fuel pump for a bed tank to fill equipment, an inverter, and a ton of lights off road. Never had any problems with it.

I threw in a 300A aftermarket when I built my motor because the stock alternator had 280k miles by that point, and I'm going to add a winch and lift gate soon, which will push the power draw higher than I feel comfortable with on the stock alternator. But if you are running less crap than a winch, lift gate, air compressor, big transfer pump, inverter, and additional lighting all at once, you'll be fine.

Sent from my FlashScan V2
 

THEFERMANATOR

LEGALLY INSANE
Feb 16, 2009
3,890
44
48
44
ZEPHYRHILLS, FL
I run the stock 130 amp ad244 in my burb, and even with all 6 lights on, both airs blasting, radio going, truck running, and the travel trailer in tow charging its batteries running the fridge, it never drops below 14 volts even at idle. I can get a replacement at any parts store, no mods needed, and runs the stock belt even. The stock ad 244 puts out some serious powerat idle to. Even on a cold start, it will pull thebatteries up to 14 volts while the glow plugs are still doing afterglow.