Great thread just put in the truck alternator in on my car,it works great ran bigger cables to the battery terminals.So thanx to the orginal poster of this for the advice working great so far.Im using a 130 amp alternator though not a 145 thats all the junk yard had but is working great.

 

Good to hear bro, where did you get the alternator from? I went to 2 junkyards and they didn't have any newer chevy trucks...

 

Im sure one will turn up by you at the junkyard,well worth it then buying new.

 

Very happy to hear this helped you, the install was rediculously easy wasn't it?? As far as the fuses being black that is semi normal, over time the current draw through the metal will show as black spots I have seen it a bunch of times ( been a tech over 10 years ) I wouldn't be concerned with that. Sounds like you did everything under the sun to fix this as I pretty much did my self and it was driving me crazy, I really started to think there was something wrong with my car but everytime I went back through all my logical diagnostic steps they led straight to the alternator. I also have a pretty fresh Optima red top and good wiring. It all comes down to cheap POS rebuild parts being the problem.... I almost bought a GM alternator thank GOD I did not or I would have really thought it was the car.


They dont have a 130 that I am aware of??? There is a the f-body and truck 105 and the truck 145. But either way, its working and thats all that counts.

guys check out this website car-parts.com ( MODS PLEASE allow the non sponsor link as this is helping many people)

If you go to that website you can search for the 145 amp alternator from a 2003 truck and it will tell you the price of the alternator and how many miles away the yard is that has it. It will also sometimes tell you the mileage on the part.



And HELL YES im really glad this helped more people than myself, this crap has been plauging me for over a year and I cant count how many times I have had to pull over halfway home at my cousins or baby the car home only to hurry and pull the alternator and call around trying to find a ride to the store to get another so I could go to work the following day....



Thank you all for the feed back this should be very helpful to many boardmembers. This is almost approaching a "sticky" vote.


Big thanks to the alternator rebuilder and board member that got my thought process going to go this route!!!

 

Added to the Howto Archive under Electronics.

 

LKQ has a couple locations near you out there give them a call they have them in stock.

or go to car-parts.com I looked up junkyards around a random san diego zip code and there were lots of places anywhere from like 10 mile to 200 miles from that zip that had them so you should be able to find one fairly close.

 

thanks bro, that link really helped. I found one and bought it and installed it yesterday, it helped because so far the car has not gone into the red when the car is idle-ling. But know i think I have a vacuum leak somewhere because my idle drops sometimes when I slow down for a stop. My car idles between 500-600rpm on the stock tach(it did that before), my next mod will be an ls6 valley cover

 

Awesome!

 

Cool glad to hear it fixed another one. As far as the vacuum leak it would make the idle go higher not lower and I believe the stock idle is somewhere right in that range anyway, like 550 maybe?? Also if you had a vacuum leak you should get a check engine light and a lean code set. I don't know for sure what the stock idle speed is I haven't had a stock idle in a couple years, mine is like 750 now.

 

I noticed mine idles between 600-700 rpm after the alternator. I almost think the engine dies because it's so quiet. Used to idle around 800-900 rpm. On the positive side, I swear my radio is louder and my ac blows harder. Maybe it's just me.

 

I had some alternator problems, and went through a few OEM ones under warranty, but the root cause ended up being a battery that was over-stressing the alternator. The car sat over the winters with battery in and no trickle charge, so the juice was dropping to around 60% and overtaxing the alternator.

Solution was a new battery. Now it's all good.

BUT, the newer GM alternators (newer model years, apparently not updated for older cars) has a better system for maintaining juice at idle with a load like heat and headlights at night, where the older alternators, in my case 2001, do not do so well. This is according to a GM Service Manager. So the original poster mentioned a newer model year alternator -- perhaps it is one with this newer engineering. The trick might be to find out when that update started?

 

Oh, well I haven't gotten a check engine light and I just did my smog and passed so maybe there is no leak.

 

Thats weird your idle is lower, mine is stil the same.. And yeah I would not doubt that your radio is louder and the a/c blows harder, those two things can pull quite a bit of amperage and the new and improved alternator will absolutely make a difference.

Well I think they stopped using that alternator when they stopped making the F body in 02. But the truck alternator has alot of benefits, such as the bridge rectifier having better/larger amp diodes. That is one of the most common failures. Also being a higher amp output alternator and the car still only using the same amount of amperage means its not as much work for this alternator, or in other words its nowhere near running at its limit, more like outputting 50 percent instead of 75 percent of its available output.

I being a tech for a long time have seen battery's pull too many amps to maintain a charge and cause repeat failures, but I checked the draw going into and out of my battery and there was only a 1 amp difference, so that means the battery was using 1 amp of the alternator's output to maintain a charge, I dont think it gets better than that.

Also I have put a ton of miles on the car since the alternator and NOT ONE of my previous issue has returned.

Sounds like your good then, enjoy the lack of stress that comes with constantly staring at your voltage gauge and watching it sink into the red, I sure am.

 

Does it have to be from a 99-2003 truck? I see listings for a 145 amp Option KG3 alternators from 2004 and 2005. Would either of these work?

 

As long as its a 4 pin connector it should. Owner at work has a 2005 Silverado and his alternator looked like the one I got.

 

I believe so if its the KG3, I was told to look on 99-03 trucks and that I would definately find what I needed, it worked for me so I went with that. Now junkyards can cross reference these things so sometimes if you order a part for an 03 if it has a compatible part from another year then that is what you will get.

So really it doesn't matter as long as you get the 145 amp, 4 pin, KG3 alternator you should be good to go. I used 2003 for reference when I bought mine. So if that alternator were in service in years later, then thats what you may get when you go to pick it up, or vice versa it could be from the earliest year put into service.

 

So it has 2 mounts instead of 3 ?

 

yes.....it only uses the front 2 bolts........the rear bracket and 2 bolts are not used as the 244 does not have a bolt boss for the bracket bolt