Alternator Replacement
#1
7th Gear
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Alternator Replacement
I'm going to get my alternator tested. I think it's showing signs of needing to be replaced. I've looked at the youtube videos showing guys replacing the alternator and it doesn't look too difficult. I was wondering if there was a huge difference between some alternators that I was looking at.
Autozone has one at 145 amp for $176 +$30 core. http://www.autozone.com/batteries-st...eVehicle=false
Same price at O'Reilly's. http://www.oreillyauto.com/site/c/de...itemDetailTab_
Corvette Mods as a 150 amp for $220. https://www.corvettemods.com/2005-20...mp_p_8257.html
Just wondering if anyone recommends or has had a good experience with a new alternator. I'm a little hesitant to get one rebuilt. It would just mean I would need to take the bus to work in the mean time. Seems like a hassle for me. Thanks!
-Andy
Autozone has one at 145 amp for $176 +$30 core. http://www.autozone.com/batteries-st...eVehicle=false
Same price at O'Reilly's. http://www.oreillyauto.com/site/c/de...itemDetailTab_
Corvette Mods as a 150 amp for $220. https://www.corvettemods.com/2005-20...mp_p_8257.html
Just wondering if anyone recommends or has had a good experience with a new alternator. I'm a little hesitant to get one rebuilt. It would just mean I would need to take the bus to work in the mean time. Seems like a hassle for me. Thanks!
-Andy
#3
Team Owner
Billet Tech is getting popular. Just some examples:
https://www.corvetteforum.com/forums...ternators.html
https://www.corvetteforum.com/forums...ternators.html
https://www.corvetteforum.com/forums...lternator.html
https://www.corvetteforum.com/forums...ternators.html
https://www.corvetteforum.com/forums...ternators.html
https://www.corvetteforum.com/forums...lternator.html
#4
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C6 of Year Finalist (performance mods) 2019
A few years ago I got questioned on how long it took me to change an alternator on my LS3. It was under nine minutes from unlatching the hood to closing it and that included disconnect and reconnect of the battery. I was not rushing, but I didn't stop for a beer either.
I suspect anyone who has the ability somewhere in the range of changing oil or sparkplugs, could easily change an alternator in 30 minutes.
My original lasted for 900 miles and was replaced under warranty by a dealer. That one made it to 51,000 and I replaced it with the same as OEM, but just not from a GM dealer. I'm currently at 138,000 and it's still kicking. Now where's the wood to knock on.
I suspect anyone who has the ability somewhere in the range of changing oil or sparkplugs, could easily change an alternator in 30 minutes.
My original lasted for 900 miles and was replaced under warranty by a dealer. That one made it to 51,000 and I replaced it with the same as OEM, but just not from a GM dealer. I'm currently at 138,000 and it's still kicking. Now where's the wood to knock on.
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SteveDoten@ARH (09-12-2016)
#5
Team Owner
You might want to check out Dano523's thread here on cleaning up an oem alternator. My bet is that there are many alternators being replaced that are not truly bad here on the forum....as there are lots of new parts being thrown at problems before a full diagnosis of the problem.
https://www.corvetteforum.com/forums...nator-fix.html
What signs are you seeing that make you think it needs replacing?
https://www.corvetteforum.com/forums...nator-fix.html
What signs are you seeing that make you think it needs replacing?
Last edited by cclive; 08-30-2016 at 07:19 PM.
#6
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#7
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I'm going to AutoZone after work to get the alternator tested. The battery was installed less than a year ago (end of December). I noticed the battery gauge running under 13 and once under 12 last week when I was at idle and had everything running (radio, headlights, windows being rolled up, etc). I replaced the battery in my key fob but it still doesn't work half of the time. I have to do the manual open from the trunk, which I hate because I just hate having the car alarm go off and making it seem like I'm breaking into the car. Since it's an 05, I assume the alternator has never been replaced. I bought the car in April and have only done some minor stuff to it. I know this might seem like not enough evidence to assume the alternator is bad but my last car had the alternator go out when it was 16 years old, so I figure it wouldn't hurt to just replace it with a new one.
#8
Melting Slicks
Actually sounds like your alternator is running normal, especially in the heat with the fans running.
Changing to the upgraded Billet Tech, you'll have much better idling voltage than the OEM.
Changing to the upgraded Billet Tech, you'll have much better idling voltage than the OEM.
#9
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I guess I am lucky since my alternator is going strong at almost 148k miles on my '05... As hoxxoh said, where is that wood to knock on???
Oh, there it is between my shoulders.
Oh, there it is between my shoulders.
#11
Burning Brakes
I'm going to AutoZone after work to get the alternator tested. The battery was installed less than a year ago (end of December). I noticed the battery gauge running under 13 and once under 12 last week when I was at idle and had everything running (radio, headlights, windows being rolled up, etc). I replaced the battery in my key fob but it still doesn't work half of the time. I have to do the manual open from the trunk, which I hate because I just hate having the car alarm go off and making it seem like I'm breaking into the car. Since it's an 05, I assume the alternator has never been replaced. I bought the car in April and have only done some minor stuff to it. I know this might seem like not enough evidence to assume the alternator is bad but my last car had the alternator go out when it was 16 years old, so I figure it wouldn't hurt to just replace it with a new one.
Last edited by RICH 28; 08-31-2016 at 10:37 AM.
#12
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The test at AutoZone showed no issues with the alternator or battery. I put the key fob in my pocket with my cell phone all of the time, so that might be part of the problem of why the key fob doesn't work. Nice to know that my battery and alternator are not the issue.
#13
You might want to check out Dano523's thread here on cleaning up an oem alternator. My bet is that there are many alternators being replaced that are not truly bad here on the forum....as there are lots of new parts being thrown at problems before a full diagnosis of the problem.
https://www.corvetteforum.com/forums...nator-fix.html
What signs are you seeing that make you think it needs replacing?
https://www.corvetteforum.com/forums...nator-fix.html
What signs are you seeing that make you think it needs replacing?
Bluntly, before you do anything, break out a multimeter and with the A/C off and the car idling, pull the voltage readings from the following areas.
1. First one is the off the back terminal of the alternator (under the rubber boot) as your positive source, and the body of the alternator as the negative source for the multi meter. The voltage should be 14.6v or higher, and if you are getting lower voltage and running stock spark plugs and spark plug wires, then see my write up listed above.
2., Check is at the battery terminals, and should only have a voltage drop from the alternator of .1V. Hence if 14.6 at the alternator, then should have 14.5 at the battery terminals.
3. Is from the terminal on the engine bay fuse box (lift the lid) and use the body of the alternator your ground source, and again should only have a .1 voltage drop from the direct alternator reading.
Note, since you are by passing the engine block ground point connection, if the battery reading (2) was low compared to the (1)alternating reading, but test 3 is fine, then the problem is a bad ground point connection to the engine block as shown above. If the low battery connection voltage (2) is the same for this test against the alternator direct check (1), then it not the ground connection at the engine block the problem, but the battery and alternator wires connection point bad at the starter solenoid where the two are bolted together (need to be cleaned and re-bolted in place on the the starter Starter Solenoid lug. If the clean up and re-bolting does not solve the problem, then the in line fuse on the alternator charging wire (just before end connector on it that bolts the Starter Solenoid termial) is bad isntead.
Note, is the starter solenoid is *****, then it can be replaced, instead of having to replace the entire starter.
https://www.amazon.com/Premium-Quali...iglink20400-20
As for DIC read out, should only be a .3 volt drop from the alternator reading. So again, if 14.6 at the alternator, should read 14.3 at the DIC. And to point out, the DIC reading is not telling you the voltage at the dash cluster, but the voltage of the ECM isntead. So here, power from the engine fuse box goes to the BCM, then is sent out of the BCM to the ECM at the end of line isntead. The signal from the ECM, to the DIC, is all digitial over the GM land bus isntead.
So more that a .3 volt drop from the alternator reading, to the DIC with the voltage on check 3 being at least 14.5volts, and the problem is not in the charging system wires under the hood, but isntead from the engine fuse box wires to the BCM, then to the ECM instead.
Last edited by Dano523; 08-31-2016 at 09:52 PM.
#14
To add, once last test with the multi meter comes in real handy as well.
With the car off, doors closed, the hood open and the hood light disconnected if your hood has one, remove the terminal from the engine bay fuse box, and with the alligator connector type wires on the multi meter and then connected into the amp side of the meter with it set to amps, connect the meter in line between the fuse box terminal, and positive wire connector you just removed from the terminal.
Note, most meters will read up to 10 amps, and make sure that you don't ground out the positive wire if you are going to set it down in the engine fuse bay.
At first, the meter should be reading just over an amp, but give it a few mins, and the reading should drop way down into the .015 amp range when the car goes into sleep mode isntead. If the meter does not drop down to the .15 amp range in a few mins, then you have a module in the car that is not going into sleep mode, and what is drawing the battery over night instead.
Note, opening the door will pull the car out of sleep mode, and don't try to start the car this way, since you will blow the 10 amp fuse in the multi meter.
With the car off, doors closed, the hood open and the hood light disconnected if your hood has one, remove the terminal from the engine bay fuse box, and with the alligator connector type wires on the multi meter and then connected into the amp side of the meter with it set to amps, connect the meter in line between the fuse box terminal, and positive wire connector you just removed from the terminal.
Note, most meters will read up to 10 amps, and make sure that you don't ground out the positive wire if you are going to set it down in the engine fuse bay.
At first, the meter should be reading just over an amp, but give it a few mins, and the reading should drop way down into the .015 amp range when the car goes into sleep mode isntead. If the meter does not drop down to the .15 amp range in a few mins, then you have a module in the car that is not going into sleep mode, and what is drawing the battery over night instead.
Note, opening the door will pull the car out of sleep mode, and don't try to start the car this way, since you will blow the 10 amp fuse in the multi meter.
Last edited by Dano523; 08-31-2016 at 10:03 PM.