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How do you all get 6.2s to 300K miles

those cigar plug adapters only are reading voltage that is going into the cab. need to get a real multi-meter and probe the batteries and on the back of the alternator.

one of these meters... you can pick up a cheap one at any auto parts that will work fine for this.

1773424927616.png
 
dbrannon79 said:
those cigar plug adapters only are reading voltage that is going into the cab. need to get a real multi-meter and probe the batteries and on the back of the alternator.

one of these meters... you can pick up a cheap one at any auto parts that will work fine for this.

View attachment 98489
Click to expand...
The cig lighters read correct voltage on everything Ive used them on
 
If your seeing normal 13.5~ voltage at high speed but goes low cruising around town, it almost sounds like a diode has failed in the alternator. at idle you should be seeing normal charge voltage (above 12 volts = 13.1+) as you increase the RPM to around 800-1000 voltage from the alternator should increase to a full 13.5 -14.1 and stay there.

on some of the older style alternators at first startup you might see a low reading until the first blip of the throttle which excites the alternator windings which then should ramp up and continue from then on even at idle.
 
jrsavoie said:
The cig lighters read correct voltage on everything Ive used them on
Click to expand...
The do read correct, They read the voltage in the cab. but we don't know if there is a difference between the power in the cab vs at the battery. GM did a poor job with wire sizing and connections going into the cab, voltage at the battery can be perfectly fine and in the cab can read low. I have seen this many times on older rigs. his alternator and batteries could be perfectly fine and may have a bad connection or something going on at the main terminal block on the firewall under the hood. Checking with a multi-meter will show this.
 
One night of leaving on the power beats up batteries yes, but lower than normal batteries should simply kick the alternator into work. And your alternator is NOT producing.
Test with a good meter at the battery. This tests the alternator and the wiring.
If it isn’t producing (which yours appears to be in bad condition) you can remove and clean the connections. Beyond that- remove the alternator itself and take into a parts store for testing off the truck.
I’m with Doug-I think the alternator is toasty.
 
Will L. said:
One night of leaving on the power beats up batteries yes, but lower than normal batteries should simply kick the alternator into work. And your alternator is NOT producing.
Test with a good meter at the battery. This tests the alternator and the wiring.
If it isn’t producing (which yours appears to be in bad condition) you can remove and clean the connections. Beyond that- remove the alternator itself and take into a parts store for testing off the truck.
I’m with Doug-I think the alternator is toasty.
Click to expand...
If you have a good rebuilder, take it there.

I'd disconnect the alternator wire check voltage at the alternator

Make sure and protect the end of the wire from arc strikes
 
Theres a literal NAPPA 7 minutes down from me.
I just need to find the receipt for the alternator.

As for the batteries (I honestly would jave warrantied them out just cause at this point) theres no Oriellys in NYC or LI

Update: i can't find it 😭
 
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nycxjeremyy said:
Theres a literal NAPPA 7 minutes down from me.
I just need to find the receipt for the alternator.

As for the batteries (I honestly would jave warrantied them out just cause at this point) theres no Oriellys in NYC or LI

Update: i can't find it 😭
Click to expand...
What kind of Napa is a literal Napa?

In my experience. Most box store electrical stuff is crap.

If you have a good case, you're better off at a good rebuilder

Crappy rebuilders are no better than box store stuff
 
nycxjeremyy said:
For reference boys, what i currently run:
View attachment 98500
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NAPA should have it on record that You purchased this alternator from them, if You registered the warranty.
If not, and, if You paid with a credit/debit card, pull up that transaction on the card account, show that to them, it might help.
And, regardless if or if not they work with You, have them test the alternator. IDK if they have the means to do an invehicle test so might want to pack the necessary tools to disconnect the batteries and remove the alternator on site.
See what their test shows.
 
MrMarty51 said:
NAPA warranty is nation wide, maybe into Mexico and Canada too, IDK about them other countries.
Click to expand...
I've been told a few times - at stores- that Napa warranties were store specific.
I guess I should have called corporate.
It's one reason I never bought a lot of Napa parts for certain things. I always mostly stayed with GM or ACDELCO. Which weren't always available at Napa anyway
 
jrsavoie said:
I've been told a few times - at stores- that Napa warranties were store specific.
I guess I should have called corporate.
It's one reason I never bought a lot of Napa parts for certain things. I always mostly stayed with GM or ACDELCO. Which weren't always available at Napa anyway
Click to expand...
Was told by the boys that NAPA parts are top of the line and out perform/out last anything AutoZone has to offer, this was also parroted by Squarebody 454 bro
 
jrsavoie said:
I've been told a few times - at stores- that Napa warranties were store specific.
I guess I should have called corporate.
It's one reason I never bought a lot of Napa parts for certain things. I always mostly stayed with GM or ACDELCO. Which weren't always available at Napa anyway
Click to expand...
NAPA is nation wide, their warranties used to be.
 
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