The fix for my endless alternator failure's
I would not recommend changing the stock one unless you have a problem with it, they are a much better product than the aftermarket ones. There may be a good aftermarket one if its custom built, but these off the shelf parts store one's are crap!
Okay so on that bracket, there is no way to mount a bracket to the rear of a KG3. There is no hole back there on the kg3 to put a bolt in. The KG3 never used a rear support. It has always mounted the exact way you are putting it on your car.
The rear bracket IS NOT to keep the alternator from moving or slipping, it's a rear brace that isn't necessary. That's an old school thing that was needed for stamped steel brackets since stamped steel brackets would flex they needed a rear support. Best I can tell they transferred the support bracket over from previous generation technology and then realized they didn't need that bracket because it isn't used on any other LS or LT platform that I know of.
On ALL the trucks and other cars it only uses the two long bolts, same bolts that the f body car has, same size and everything.
There is no moving or coming loose that happens. The mounting pads on both alternators and bolt sizes are the same, that's why this is a direct swap. That and the plug plugs right in. This is a direct swap that uses all factory stuff that needs no modification. Because it is all oem, so it also lasts like oem fit does and doesn't cause issues.
The little L bracket is a F body alternator only thing. The F body alternator has a hole in the back of it for the bracket. The truck does not. This bracket was a design transfer thing that transferred over from 80's and 90's cars that used stamped steel brackets. They had to have a rear supports on them since the stamped steel brackets would flex and needed additional support. On those style they would brace the rear of the a/c compressor, alternator, ps pump everything. But as time went on with aluminum brackets they stopped using rear support brackets on most of those items.. None of the newer cars use the rear support on the alternator bracket either, or the trucks. And they're all fine.
There have been no long term issues mounting it the way laid out here in this post on F body cars. I made this post 11 years ago and not one single issue has been reported.
Last edited by 00pooterSS; May 3, 2021 at 10:57 AM.
That's the only issue I have ever seen from not running the support brackets. But since that time the mounting brackets have become much more substantial in size and... beef. So the newer stiffer brackets seem to make it to where the rear brace is not necessary.
The 4th gen f body came out earlier than most of the LS platforms and used that bracket. The later LS platforms do not use it. I assume the c5 vette might, since it came out a year earlier than the f body. But in any case all the newer stuff does not use a support and the alternators do not even have a hole in them for it to be an option if you wanted it to.
I originally had concerns about not using that bracket but after a few years of running that alternator and this thread going on for years with no issues with my personal car or anyone else's, and seeing that gm went away from it, I'm going to say the bracket is unnecessary.
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I think for me the upgrade is worth it. The new alt is bigger and heavier fyi
https://www.hawksmotorsports.com/199...r-powermaster/
150 amp and it looks like it might have the mount for the rear bracket and third mounting bolt, though it's hard to tell without a picture of the rear.
I don't know what "One-Wire Capable:No" means, though.
Here's another one with 175 amp output and says it's "1-wire or OEM" and fits the LS1 98-02 generation.
https://www.tuffstuffperformance.com...us-8242nd.html
Last edited by ArcticZ28; Sep 12, 2021 at 07:10 PM.
FWIW if your looking for the AD244 they did come with 4Pin connectors on the mid 200 Vans it turned out. I bought a junkyard L59 to get all the external stuff to dress the L33 long block I put in my jeep (200 was way cheaper than chasing all the front brackets and ignition brackets etc down...

I got a junk yard KG3 alternator from an 03 Silverado.
some observations…
1) take off all the bolts AND the alternator bracket. It’s so much easer just to take off the front alternator bracket. It’s only 1 more 15mm bolt and it’s easy to reach! I couldn’t get the alternator past the sway bar until I took the bracket out and then it was easy.
2) The 4 pin harness that has the exciter wire is a PITA to find. Unbolt the alternator and remove the bracket to give yourself some room to work…The image below shows the orientation of the alternator when it’s mounted in the car. The bottom is towards the ground.
the yellow square is where the 4 pin connector attaches. It inserts from the top down. The small blue shape is where the retaining clip is. You can use a short screwdriver from underneath the car to gently pry the retaining clip and the whole connector comes out super easy. Just insert the screwdriver from the bottom and pry the connector, lifting it towards the back of the car. Super easy once I figured it out…
3) The freaking battery charging cable is another PITA to get off. It’s mounted tight! When you try to loosen it, the lower nut spins as well. There’s a small plastic “stop” on the casing of the alternator. Turn the nut counterclockwise until the cable and ring terminal hit the stop, and then a sharp turn and the top nut comes right off! I couldn’t even get it off with an impact until I used the plastic “stop”, and then it came off with a 3/8” socket driver no problem.
4) If your PS pump is leaking a bit like mine (even after a rebuild…) consider making a shield for your alternator out of sheet metal. There’s room to do it (barely) and it’ll keep your alternator from being ruined again…I didn’t do it because it was so late and I was tired, but it could be an easy fix. I’m not looking forward to pulling the PS pump again…
https://www.summitracing.com/parts/p...saAnhMEALw_wcB
https://www.summitracing.com/parts/p...saAnhMEALw_wcB















Still "improperly installed", but closer.