Quick 2004 F150 alternator ???

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7,500
2004 rust bucket F150 with 6 cyl. engine. My coworker showed up at work with flickering battery light. Battery is below 12V. Voltage at battery, engine running is below 12V. Directly out of the alternator output cable is reading 11 volts while running. Is this an accurate test of bad alternator? Solenoid? He's dumping the truck this year. Which local parts store alternator might be o.k.? Advice appreciated. Thank you!!!!!!
 
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This is a good design of alternator. The auto parts rebuilders are pretty good at them, a parts store unit should be fine. Rod
 
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I bought a new alternator for my 1991 F-150 from O'Reilly a few months back. The guy came out and tested it, and told me it was shot. (I was running off the battery). They ordered me one, and it came to the store a couple of hours later. I installed it with a new serpentine belt, drove it over, he checked it again, and it was good to go. I haven't had any issues since. I don't even remember what the brand was. I do know it was brand new, and not a rebuild.
 
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Originally Posted by billt460
I bought a new alternator for my 1991 F-150 from O'Reilly a few months back. The guy came out and tested it, and told me it was shot. (I was running off the battery). They ordered me one, and it came to the store a couple of hours later. I installed it with a new serpentine belt, drove it over, he checked it again, and it was good to go. I haven't had any issues since. I don't even remember what the brand was. I do know it was brand new, and not a rebuild.
Ultima Select smile those are good alternators. The rebuilt ones can be iffy.
 
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2,482
Originally Posted by dogememe
Originally Posted by billt460
I bought a new alternator for my 1991 F-150 from O'Reilly a few months back. The guy came out and tested it, and told me it was shot. (I was running off the battery). They ordered me one, and it came to the store a couple of hours later. I installed it with a new serpentine belt, drove it over, he checked it again, and it was good to go. I haven't had any issues since. I don't even remember what the brand was. I do know it was brand new, and not a rebuild.
Ultima Select smile those are good alternators. The rebuilt ones can be iffy.
I replace my 97 F-150 with one of those about 10 years ago and it is still working.
 
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Load test the battery first before condemning the alternator. Load test is NOT voltage test, it measures the amp-acity of the battery. Once you are sure that the battery is good, then load test the alternator to see if alternator is bad. Also make sure the low voltage is not caused by bad cables and terminals.
 
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Originally Posted by dogememe
Ultima Select smile those are good alternators. The rebuilt ones can be iffy.
That's it. I had kept the box, but tossed it when we moved. I did kept the various wiring connectors, plugs, etc. they included with it.
 
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Originally Posted by JMJNet
Load test the battery first before condemning the alternator. Load test is NOT voltage test, it measures the amp-acity of the battery. Once you are sure that the battery is good, then load test the alternator to see if alternator is bad. Also make sure the low voltage is not caused by bad cables and terminals.
Thanks everyone. JMJNet, we swapped in another known good battery to eliminate that possibility. We still could not get a good volt reading at the battery or at the alternator. Checked cables and connections. My co-worker had Advanced Auto order one in from the regional warehouse. Did NOT check the unit at the store (Big No, NO). Got back and discovered a mounting casting completely broken off. GRRRRRRRRRR, LOL, a typical Monday! Another replacement due Tuesday a.m.. Everyone else had them in stock, but already paid for AND core unit turned in and sent back. He's going cheapest local possible because truck will be sold in a few weeks. Goodness, even tortoise speed me could remove this alternator in 15 minutes. A scan tool check showed no DTC's. Is this normal???
 
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