Hi Folks i have a small problemni have a 2000 gmc sierra ExCab Step Side i have somewhat of a sound system on it and when ever i have it a really loud volume lever my batery reading goes all the way down to about 10 or 11 volts and my lights dim some what when ever the Bass hits. so i tought to myself oh ill just put the bigger Alternator in my truck since the stock was the 105 amp so i bought the 130 amp replaced it and put a new 130 amp belt on it now my battery truck light comes on any suggestion should i go back to he 105 since the light did not come on with that Altermator it cant be my battery it reads fine and its like 8 months old in a Napa Auto Parts Orbital < Gel Battery. engine size is 4.8 V8 power lock and power windows what do you guys suggest thanks in advance for the imput.

 

Well my friend, it sounds to me like you need an audio capacitor. Also, when your bass hits hard it isnt taking power from you alternator, its sucking it from you battery. So you might want to go with an optima red top gell cell.. not only will that battery crank over your truck for hours on end, it will definatly hold up to that bass.. heres pretty much what an audio capacitor does:
Audio capacitors store that necessary power your amplifier will need to punch those big bass notes while limiting clipping. They store power during intervals when it is not required, which is most of the time, and release it when momentary peak demand exceeds what is available from the car's power system. Along with an adequate basic power supply, a stiffening capacitor for your amp is the simplest way to be sure your system always gets every bit of current it needs. From the smallest 0.5 farad, to the 3 farad model by Legacy, there's a capacitor suitable for your installation. Mount them as close to the amplifier as possible, and choose at least .5 farad (500,000 microfarads) per 500 watts RMS of power output. You can use as many farads as you wish, but just the number indicated by the formula above is all that is necessary.

you can get these anywhere, they almost look like a huge ignition coil, or a can of spray paint.. If you have any more questions feel free to ask.

 

Well i was reading on the fullsizechevy.com and alot of them had talked if you havea sound systems you need to up size your wires from your battery to alt. battery to ground and i would have to look up the other one.

 

Heres one of the posts.

http://www.fullsizechevy.com/forums/...e+battery+wire

 

Heres another.
http://www.fullsizechevy.com/forums/...e+battery+wire

 

yes switch back to the original alternator and pick up a capacitor and wire that in. once all done unplugg the battery and zero out the computer this should take care of the light and keep it from coming back on.