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hex0rz

Alternator?

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Measuring AC voltage at the alternator. Getting approx. .01 to .02 volts. Sometimes it will spike up to .05 volts AC. Is the alternator diode going out? I'm occasionally getting the hunt at 45-50mph. When the grids cycle, the AC volts are in a pretty good swing, too. But obviously they are not cycling at that speed anyways. Just wondering what your guys' thoughts were to it, as I sure hope its not the TC!

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If you can feel it hunt, its not the converter. you can test it by pulling and isolating the field wire from the alternator, driving a bit on batteries and see if it still hunts. Though, I will say that I did have this issue from another source of noise. I would get AC when the truck was not running by the key was on due to a backfeeding relay in the AirDog wiring.

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Measuring AC voltage at the alternator. Getting approx. .01 to .02 volts. Sometimes it will spike up to .05 volts AC. Is the alternator diode going out? I'm occasionally getting the hunt at 45-50mph. When the grids cycle, the AC volts are in a pretty good swing, too. But obviously they are not cycling at that speed anyways. Just wondering what your guys' thoughts were to it, as I sure hope its not the TC!

Still under 0.10 AC Voltage...

I would unhook the field and the alternator fuse as well... Test drive.

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Alright, so 'am I right to assume the field wire you speak of is the wire on the back of the alternator with the stud? I unplugged that one and the other one as well. I took the 140 amp fuse out from the main fuse box on the driver side as well. I did notice a slight difference in shifting. But it did not hunt between 3rd and 4th.Hooked it back up to head back home and had no hunting. It did shift a little differently than when it was not hooked up, though. Thing is, it only happens occasionally. Its not a constant thing. So I'm wondering if it is the alternator or something else?I do not even have enough money at the moment to spend buying a new alt. so I'm gonna have to go on it until then even if it is the culprit. I'm just curious as to what damage it could cause if left alone?

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On the damage point mike, from what I read... Most of the parts are not rated for any real VAC from what I understand, and most won't be harmed. However, the integrated circuits of the ECM, PCM, Juice, and gauges won't live long. Edge told me that their juice modules can handle 18V (and 18-13.5=4V) but any noise that peaks past that will burn out a juice module. Also, most multimeters won't pick up the absolute peaks unless it is a flukemeter. I was seeing past 30Vmax on a flukemeter and only 13-19VAC on a normal cheap multimeter.

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Well, I was able to swing the money for an alternator. I had O'reilly's bench test it for me and every test said it passed. But the guy that tested it said it sounded like the bearings were on its way out and something about how it makes a noise initially when it first takes on a load. So who knows, maybe I just did a preventative maintenance thing... I did notice the charging rate is much quicker now, though.The truck shifts fine and don't notice a difference in driving. Heres to hoping that I don't get a hunt! :pray:I'm going to check for AC voltage leak before I go much further as well just to make sure its not "DOA."

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