Alternator Question

[landmine]

Hey guys I'm a bit stupid when it comes to the electrical systems on vehicles. I've got a 2004 GMC Sierra 1500 with a 5.3. It's bone stock other than the silverstar head lights. My question is about the alternator amps. Is the stock alt got enough to be able to use electric fans and a brake controller or do I need to get a higher amp one?

[jblakeney]

I am guessing you have the 105amp one on the truck currently. Sounds like it would be enough for your use. But it is always better to have to much than not enough. The 145amp is a bolt up and plug up unit from the 105amp.

 

I did it on my 2500....... 2 bolts, 1 nut, 1 plug....... Instant 145amps... But I have a winch on my car hauler. With 2 group 31 batteries. I use the center pin to charge the group 31's while driving. Now I had to run a wire from the rear of the truck to the front and tap in to the red box below the alternator. But that is why I upgraded.

 

Jbo

[Rosedog]

I am guessing you have the 105amp one on the truck currently. Sounds like it would be enough for your use. But it is always better to have to much than not enough. The 145amp is a bolt up and plug up unit from the 105amp.

 

I did it on my 2500....... 2 bolts, 1 nut, 1 plug....... Instant 145amps... But I have a winch on my car hauler. With 2 group 31 batteries. I use the center pin to charge the group 31's while driving. Now I had to run a wire from the rear of the truck to the front and tap in to the red box below the alternator. But that is why I upgraded.

 

Jbo

 

 

Okay so I was goint to ask this question too (about upgrading to a 145amp output). So I should be able to mount/bolt up right in the stock location as the 105amp? The belt should be the same then too, correct?

 

Mine is an 03, 4.8l though.

[Diesail]

105 amp is plenty. Don't worry about it unless you see your lights dimming when you hit the brakes

[Rosedog]

^^ I've heard that more than once but I would like to go higher if everything will bolt up in the stock 105 location.

 

There are more than enough times where I live that I'll have almost all my acc. running at the same time and have dimming going on.

[redvett]

My 04 has Silver-stars,brake controller and much more, the 105a will do fine as long as your battery is up to snuff.

[Z'06]

My '06 came from the factory with the 160-amp alternator (KW1). You could also buy an ASP 32% overdrive alternator pulley from Summit Racing or Black Bear, to name a couple of sources off hand, which would raise your alternator output by 32% (obviously).

[jblakeney]

I am guessing you have the 105amp one on the truck currently. Sounds like it would be enough for your use. But it is always better to have to much than not enough. The 145amp is a bolt up and plug up unit from the 105amp.

 

I did it on my 2500....... 2 bolts, 1 nut, 1 plug....... Instant 145amps... But I have a winch on my car hauler. With 2 group 31 batteries. I use the center pin to charge the group 31's while driving. Now I had to run a wire from the rear of the truck to the front and tap in to the red box below the alternator. But that is why I upgraded.

 

Jbo

 

 

Okay so I was goint to ask this question too (about upgrading to a 145amp output). So I should be able to mount/bolt up right in the stock location as the 105amp? The belt should be the same then too, correct?

 

Mine is an 03, 4.8l though.

 

 

I have always tried to error in the way of good. An underpowered alternator has an expiration date. If your alternator goes down.... Switch up to the 145 unit. Note that also changes your main drive belt *serpentine belt*.

 

I changed mine simply because I was running the winch with the truck off and it would pull on the batteries pretty good.... The higher amp unit will charge the 2 group 31's back up a little quicker plus I don't have to worry about burning it up (I use the center pin for 12 volt positive charging on the trailer). Heated seats, heated mirrors, heated rear glass, wipers, power windows, fuel pump, headlamps, tail lights, plus the 4x 100 watt spot lights on my trailer, winch, etc, etc, etc, etc, that takes quite a pull on the battery and alternator.

 

Jbo

[pm26]

I happen to have an OEM AC/Delco 145 amp alternator, which I purchased from gmpartsdirect. It was never used and it is still in the box. The part number is 10392759. Ask M3Dale if this one will fit your truck. It fits a 5.3 liter 2006 model. If you want this one, make me a reasonable offer. I will let it go for a lot less than the original price from gmpartdirect plus shipping.

[Rosedog]

I happen to have an OEM AC/Delco 145 amp alternator, which I purchased from gmpartsdirect. It was never used and it is still in the box. The part number is 10392759. Ask M3Dale if this one will fit your truck. It fits a 5.3 liter 2006 model. If you want this one, make me a reasonable offer. I will let it go for a lot less than the original price from gmpartdirect plus shipping.

 

I could be possibly interested as I finally just changed mine out. Do you know if it would fit in a 2003 4.8?

 

My venture into changing this has helped me out so far ( http://www.gm-trucks.com/forums/index.php?showtopic=112397 ) but I'm not sure how long it will hold up.

[wes335]

Hey pm26, are you still willing to sell that alternator?

[nickvrebel]

I made the upgrade on my 2003. I went from the 105 to 145

 

I had electric fans and a small subwoofer amp in the truck.

 

I noticed a severe drop in voltage when the fans would turn on or when bass hit (keep in mind, this was just a small amp).

 

after the swap the voltage drop was less, but if you watched closely it could be detected.

 

do you need to? probably not. would it hurt? certainly not.

 

All you need is the new alternator and a new Serp. belt, reuse mounting bolts, plug in and go.