Replacing the stock alternator
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From: Woodstock, GA
Replacing the stock alternator I did the big 3 and popped in a rebuilt Duralast 
Alternator - only because it was free on a lifetime warranty. I haven't driven it yet, but at idle I can see it drop to 12V and jumps back up.
Can someone confirm that this will work in the `99 Trans Am: Looks like a 250 A, 6 rib, 4 pin alternator.
5.7L 350Cu. In. V8 GAS OHV Naturally Aspirated
Alternator - only because it was free on a lifetime warranty. I haven't driven it yet, but at idle I can see it drop to 12V and jumps back up. Can someone confirm that this will work in the `99 Trans Am: Looks like a 250 A, 6 rib, 4 pin alternator.
1999 Cadillac Escalade
Base Sport Utility 4-Door5.7L 350Cu. In. V8 GAS OHV Naturally Aspirated
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Joined: Nov 2011
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From: Woodstock, GA
I did the big 3 and popped in a rebuilt Duralast Alternator - only because it was free on a lifetime warranty. I haven't driven it yet, but at idle I can see it drop to 12V and jumps back up.
Can someone confirm that this will work in the `99 Trans Am: Looks like a 250 A, 6 rib, 4 pin alternator.
5.7L 350Cu. In. V8 GAS OHV Naturally Aspirated
Alternator - only because it was free on a lifetime warranty. I haven't driven it yet, but at idle I can see it drop to 12V and jumps back up.Can someone confirm that this will work in the `99 Trans Am: Looks like a 250 A, 6 rib, 4 pin alternator.
1999 Cadillac Escalade
Base Sport Utility 4-Door5.7L 350Cu. In. V8 GAS OHV Naturally Aspirated
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From: Woodstock, GA
So ... first time driving this car to work in over a month and I was watching my voltage gauge jumping around from over 13 down to 10. At one point - my check gauges light came on half way to work (20 miles). No rhyme or reason why it drops unless the crap Duralast is the culprit; I can't imagine an alternator doing that. It seems to be a connection issue. I have a new exciter pigtail that I'm going to put in today along with the powermaster. Hopefully my woes might help someone. Glad to have a boss that's cool with me working remotely today!
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Thread Starter
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From: Woodstock, GA
I thought about prying it or removing the line and bending it ... or getting abusive with it to get 1/8" and elected not to. I wouldn't like knowing I'm only 1/8" of a fireworks show - especially for an oversized alternator with no rear support.
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From: Woodstock, GA
Actually that 48137 would have been fine if the charging post were elsewhere.
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From: Woodstock, GA
I thought I'd chime in here. I spoke to Ed over at Powermaster and that alternator can be clocked so that the charging post isn't on those lines. I appreciate that stellar support. I'd much rather go with that unit - so I'll be doing some clocking later!
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From: Schiller Park, ILL Member: #317
Please let us know if the 48242 is correct once you get it.
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From: Woodstock, GA
Interesting; you are correct about what Summit's site shows. I wonder if Powermaster part numbers have changed over the last decade? I just looked back into my records from 2012 and found that the number I posted above was correct for LS1 F-body, back then, but it seems to be different now. So I will remove my reply in the other thread, just in case this number is no longer valid for this application. Odd that they would change part numbers though.
Please let us know if the 48242 is correct once you get it.
Please let us know if the 48242 is correct once you get it.
Staging Lane
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From: STL
Thread Starter
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From: Woodstock, GA
Yeah ... that 165a looks to be just like stock in size. The larger 220a took a bit more work getting it in. That's one reason why I'm going to stick with it. I'd hate for my sweat to be for not! It'll be worth another 55 amps too!
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From: Schiller Park, ILL Member: #317
165amp is plenty for most any electrical demand that a 4th gen F-body will see (unless you have some kind of insane audio system). Those extra amps won't be used or needed with stock/near stock accessories.
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From: Woodstock, GA
You're right about that. I do have a pretty good system. It's a Rockford Fosgate 5 channel 600W rms .... so it'll be sucking 40-50 amps when I'm hitting it hard.
