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alternator?

3K views 8 replies 5 participants last post by  Machster69 
#1 ·
was wondering if my alternator is going have noticed a whinning sound coming form engine area
i have noticed a drop in how fast truck starts
this morning truck wouldn't start
got home put a charger on gave it a few minutes and it fired right up
i check battery vols was 12.4
when i started truck i put a volt meter on alternator was putting out 14.5
so isat in truck and held idle up a little i didn't see any movement in meter in dash
but i did notice the whine had wife sit in truck so i could listen
any info
would be great
i looked at battery it's a napa but they didn't popout date so i can't tell when it was bought
truck is a 2004
4x2 ext cab 5.3 v8 :shock:
 
#4 ·
I would also have the battery load tested the slow crank could be because the battery has a dead cell a volt meter will not tell you that.
 
#5 ·
+1 on the battery check. A lot of places like Napa or Auto Value will test your battery for free to see if it has a dead cell or something. Also, as mentioned earlier, the "remove the positive cable" while the truck is running is a good check to make sure the alternator is working up to snuff too
 
#7 ·
If battery was charged up, when doing this it will keep vehicle running for a little while until it drains the battery. Turn on headlights, dome light, etc. to help speed up the process of draining battery. Also keep an eye on those lights and if they start dimming, then it's the alternator. You can stop the procedure before completely draining battery.
 
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