I was on my way home from nebraska to ohio and my alternator guage started hitting below the N on normal and then 3 or 4 minutes later down the road it would go back to the regular spot. This continued for about 4 or 5 hours and i made it home. Then when i got home the alternator guage would run real low like on the N in normal instead when it was usually on the M. I could still drive my truck so i kept driving it until it stopped holding a charge. Is this my alternator or my voltage regulator can anyone help me please. I have a young child and cant afford not to have a clue of what i have to change. THANKS YOU GUYS ARE ALLWAYS THE BEST!!!! My friends all told me when an alternator goes out it usually just goes out but i am not sure.

 

My alternator started doing the same thing for a while and then it went dead. The needle would bounce around, sometimes my battery would be dead and sometimes not. Then boom, dash needle shows nothing and dead battery. I would have rebuilt mine (GMC Suburban) but the brushes were soldered in and I didn't feel like cutting things. The brushes in yours have probably wore out, or are almost wore out. Just drive over to Autozone and they'll test your alternator for free. Just describe the symptoms to them. That way you won't have to afford a clue as to whether or not it's the alternator, it'll be free. And if you're able to take things apart and put them back together, you can probably just rebuild yours for $10-20 with a rebuild kit. Otherwise you'll have to buy one and they're over $100. The rebuild kit for my Suburban was $35 (crazy) but a new one was like $150. I've rebuilt them on an old Datsun pickup I owned way back and on an 81 F100 I once owned and it was a snap. Replace brushes and bearings and it's like new.

 

If you have a technician test the alternator and confirm it is broken, make sure it gets replaced with a third generation alternator. A second gen alternator is prone to burned wiring, poor output, and is generally not a good alternator for any Ford Truck!!!! If your alternator has two plastic plugs attached to it, and if it has an external fan ( you should see the external fan right under the belt-driven pulley), Then it is time to upgrade the alternator to a third gen. This requires wiring changes at the alternator, and nothing else. The 3rd gen alts don't cost much more than what I think you have. The output is stronger, and it should last 100,000 miles if you buy one from a reputable store.

Please stay away from discount auto parts stores!! Pep Boys especially! I know from personal experience the lifetime alternators from Pep Boys are very poor quality. If your current alternator is under warranty and a 2nd generation, it is worth it to just forget the warranty and upgrade your alt to the newer series.

Check your local yellow pages for a shop that specializes in starters, generators and other automotive electrical parts. They will usually use good parts, they should be able to install a new 3rd gen alternator in 20 minutes, for about 200 dollars.