Akbmsoe

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

timd38

I spent the extra money and got a Billet Tec.

Not a fan of rebuilt or Chinese new alternators and starters.

RicK T

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

HOXXOH

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.

cclive

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?

cclive

I would grab a martini and spend 30 minutes doing it...LOL

Akbmsoe

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.

extrapilot

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.

LJD51

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.

jesse82nc

Loving my Billet Tech. I see a good 14.3-4V at idle now most of the time. Even with plenty of stuff on in the car.

RICH 28

Your cell phone in your pocket with the fob could cause problems with the fob not working all the time. My voltage readings are all over the place like yours, but I only had to replace the car battery once in 11 years of ownership. Do you get a "service charging system light" on? If not , you should be okay. What were your test results from Autozone?

Akbmsoe

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.

Dano523

Yep and once you have that completed, double check the connection point on the starter solenoid and the ground to engine block as well.



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.

Dano523

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.

Akbmsoe

Great info! I'll take a look when I change the oil soon. Thanks a lot!