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145 Amp Alternator Will Void The Warranty?

M

MikesAvalanche

SM 2003
Full Member
Joined
Aug 4, 2002
Messages
91
Location
South Texas
I need some help!! How could changing the 105 amp to a more powerful 145-amp generator void the warranty? How would the installed 145 amp alternator hurt the electrical system and void the warranty? :7:

I have been having a battle :8: with the dealer I bought my AV from, Gunn Chevy here in San Antonio. They said that GM will void the warranty if they or I install the 145 amp alternator because it will cause a power problem. Doesn?t the regulator control the electrical flow?

Could someone help me out on this, needless to say I do not believe the dealer. ??? ???
 
Mike,

I'm fairly sure that each warranty claim needs to be judged on it's own so it will depend on what the claim was and which parts were affected. For example if you changed the alternator and then had a problem with the rear differential they couldn't disallow the claim and use the new alternator as the reason.

Conversely if you fitted a new alternator and then tried to claim a damaged regulator I would think they would disallow that, even though I don't agree.

I think you should try and track down a few things;

1. What parts are different when you order the snow plough prep package, and

2. Seek come advice from your local consumer protection bureau.

If the only difference in the snow plough prep package is the alternator and they use the same regulator then the dealers advice just deosn't hold water.
 
Skidd said:
I think you should try and track down a few things;

1. What parts are different when you order the snow plough prep package, and

2. Seek come advice from your local consumer protection bureau.

If the only difference in the snow plough prep package is the alternator and they use the same regulator then the dealers advice just deosn't hold water.
Click to expand...
This is what I left them with. I asked what will it take to make my AV like the one's that come with the snow plough package without the plough.

Thanks for your advice!
 
I don't know the details of the vehicle, but electrically, if the system is set to handle 100 amps, and you provide 145, you may overload electrical components or even the wire. At a minimum, the larger alternator may use a larger wire in the harness or a different regulator, etc. etc.
 
I believe the snowplow option comes with a 145 amp alternator straight from the factory.
 
Why would GM void your electrical warranty after increasing the alternator size. This is to allow them to get out of there responsiblities and the new part is not covered by factory installed warranty. However, if you do increase the alternator size, precautions need to be taken.
First, you have increased the current capacity by 45%. The wire from the alternator back to the battery (probably through the starter connection or to the main electrical connection) was probably not rated for 145 amps....thus will need to be increased to 145amps or larger.
Secondly, why are you telling the dealer what changes you are going to be making. This is information that they like, as they will be more than happy to cancel your warranty so that they get paid from you directly. As they will charge you more that GM, and they have the money sooner....

Enjoy Modding.....
 
I don't think you'd have to upgrade any wiring, unless you plan on pulling all 145amps...

Most people seem to get these, 'just in case'... ?They'll have a few extra lights and what-not on their truck, but will mainly get the higher output alternator so their lights won't dim on idle.

If you're running a stereo system with it, you won't need to do much... Mainly upgrade the wire from the alternator to wherever it happens to go... (is it still the starter and battery?) ?Either way, just what dichris said.

I thought the 145 rating is what the alternator is 'capable' of. ?If it's a single wire, GM alternator... the power limiting circuit is built into the alternator itself. ?It's going to put out a healthy 14-15 volts like a standard alternator, but only as many amps as the whole electrical system needs.

I had an amp-meter in my old muscle-car. ?When I'd start the car, you'd see the amps jump to a charging 25 to 30. ?After about thirty seconds, it's slowly come down to 0. ?No charging, no discharging. ?The running engine and alternator were providing a perfect balance of power needed... it wasn't just pumping out 100+ amps full-time.
 
I've got to add onto my last post a bit... it's been a while since I did electronic stuff!

Yeah, your typical one-wire GM alternator will have a single wire coming off of it, and going right to your battery or power distribution block (or whatever they're calling it these days). ?

From the battery, you'll have the huge gauge wire for the starter and ground. ?(The starter sucks a HUGE amount of power, and the heavy gauge wire helps deliver it as efficiently as possible)

So basically, all you should have to upgrade would be the single wire coming off the alternator, and any wires which will be using large amounts of power (they should actually already be large enough to begin with, if the installation of the acessory was done properly). ?

Sometimes the positive starter cable, and alternator lead are a one piece deal. ?You can cut out the old alternator lead and add in your own, or hunt down a heavier duty set.

Also... remembering now... the amp-meter in the car was attached between the battery and power distribution block... It was only looking at power being exchanged by the battery, not what was coming directly out of the alternator. ?:cautious:

I'm not sure how much power a typical running engine uses... ?Especially with everythig being computer controlled now.
 
carsdirect.com shows the 2003 2500 snow plow prep package with a 145 amp alternator at a cost of $166. Great price if you need it and order it with the vehicle.

I am still wondering about the 16x7 wheels on the 2003 2500. It seems specs may have changed from 2002 to 2003 or people have their numbers mixed up.
 
Marc_w,
You always match the wire to the source. Your thinking is what causes electrical fires in cars, houses, etc (i.e. never planning on USING the maximum power). A typical home repair that is made is when a homeowner has a problem with a breaker that keeps tripping and replaces it with a larger breaker. Now, somewhere in the wall the wire will overheat and burn. I don't know what size wire Chevy installed, but I would not install a larger alternator without verifying it is correct. An example of drawing the maximum power from your alternator is when you jumpstart another vehicle with a dead battery. This typically CAN fry your vehicle, and having a too small wire will not help.
 
It is wise to check the above wires and verify the current capacity - if an upgrade is indicated, they are inexpensive and easy to install.
 
Terminator said:
Marc_w,
You always match the wire to the source. ?Your thinking is what causes electrical fires in cars, houses, etc (i.e. never planning on USING the maximum power).
Click to expand...

Yeah, but if we did this, we'd be running 0 or 2 gauge all over the car like the starter and ground are using. ?:cautious:

I always use wire rated 'over' the max current the particular component will pull, and use a inline fuse rated for the actual max...

I don't know what size wire Chevy installed, but I would not install a larger alternator without verifying it is correct. ?An example of drawing the maximum power from your alternator is when you jumpstart another vehicle with a dead battery. ?This typically CAN fry your vehicle, and having a too small wire will not help.
Click to expand...

Yeeaah, it's always good to check. ?

I know it's very popular in the audio world to upgrade alternators. ?As far as I've heard, they're all drop in installations.

The only circtuit really related to jumpstarting another vehicle would be the positive from the alternator to the battery itself, and the vehicles ground. ?The rest of the car (like radio and dash wiring) would not be affected because the current isn't being pulled through there. ?It's just off to the side waiting patiently.
 
Terminator said:
Marc_w,
You always match the wire to the source. ?Your thinking is what causes electrical fires in cars, houses, etc (i.e. never planning on USING the maximum power). ?A typical home repair that is made is when a homeowner has a problem with a breaker that keeps tripping and replaces it with a larger breaker. ?Now, somewhere in the wall the wire will overheat and burn.
Click to expand...
Actually, if you re-read marc_w's post, you'll see that he is advocating the opposite of what you say.

When replacing the alternator with a higher capacity unit, it's the heavy gauge wiring between the alternator and the battery that will take an increase in current. That is why he was recommending to increase the size of the cable. This is because the increased alternator capacity can increase the charging current that is available to the battery.

The rest of the vehicle wiring is not an issue. The current flowing though those wires is a function of the load on those wires, and not the maximum current capacity of the alternator. Just because the alternator can supply more current does not mean that the loads on the far end of the wires will draw more current. This is assured since the voltage output of the new alternator is the same, the load will not see any difference.

Adding the higher capacity alternator will not stuff more current down the existing vehicle loads than before, it will simply allow additional loads to be added (assuming that they tap in at the alternator, or at the battery after a larger alternator/battery cable was installed.)

The rest of the vehicle wiring is still protected by their fuses and fusible links, as these are not being changed.

To return to your house wiring example: this is not a case of increasing the circuit breakers while leaving the wiring untouched. This is equivalent to upgrading the electrical service to your house. For example, to go from a 100 to 150 amp service, the cable from the pole to the house needs to be upgraded with a larger one, and a new main breaker needs to be installed (and possibly an additional breaker panel.) However, none of the branch circuits are changed: the wiring for these and the associated breakers remain the same.

-- SS
 
it will allow additional loads to be added (assuming that they tap in at the alternator, or at the battery after a larger alternator/battery cable was installed.)
Click to expand...

Don't forget that the alternator is THE source of current for the vehicles electrical requirements, until its potential is fully tapped. In the case of a spike in requirement, the alternator has no "headroom" so to speak, meaning it can't momentarily produce 180A rather than the 145A it's rated for. This is the point where the battery picks up. All loads will be tapped in at the battery, as it is the secondary source of power once the alternator can't keep up with momentary demands.

I notice no one has mentioned upgrading grounds for the electrical system as well. Since the chassis is the ground plane, the ground wire should be at least of equal size to its counterpart.
 
DS said:
All loads will be tapped in at the battery, as it is the secondary source of power once the alternator can't keep up with momentary demands.

I notice no one has mentioned upgrading grounds for the electrical system as well. Since the chassis is the ground plane, the ground wire should be at least of equal size to its counterpart.
Click to expand...
Both are very good points. (y)

I stand corrected. ;)

-- SS
 
I went to Bike show today, and GM had an AV at the entrance. Had a look at the alternator and found the the load carrying wire from the alternator was only about 8" inches long from the alternator to the Main cable connection. As the connection tapped into the main cable from the Battery to the starter. This cable (Battery to Starter) can easily carry the capacity of the larger alternator as the cable is rated for the starter. So, if you want to replace the 105 amp with the 145 amp alternator, you should also replace the lead cable, which you should be able to order from GM, the cable should be for 2500 AV with snow plow option. I do not have part #, sorry.....
As for the other electrical connector on the alternator for the regulating of the voltage by the computer and the 12 volt supply, I can only presume that both alternators have the same connector....
I cannot see how the dealer or GM can cancel your warranty, other than the warranty on the alternator. The new 145 amp alternator should have warranty from GM dealer as a part warranty, and I believe that is usually about 90 days.....

Mod on!!!!!!
 
The only wire you need to be concerned about is the the one from the alternator. The power capacity of your battery is much greater than the output of the alternator. Try shorting the battery to ground and see what happens. If the voltage was higher you could easily weld with your battery. The house circuit analogy is accurate. Just because the nuclear power plant is rated in megawatts doesn't mean you need 4/0 cable on your table lamp.

Everything down stream of the battery is rated for load. The truck would way a ton more if the wiring needed to carry the output capacity of the battery.
 
had my 105a alternator go out last night(dang mud...) and i was getting irritated with the old guy at autozone because he claimed a 145a simply would not work. after reading this very informative thread, i feel much better about stressing to him that a 145 would work fine. unfortunately, i had to get it running tonight and my dinky store didn't have a new 145 in stock.
 
Wow this is a old post, I have had mine on for years, don't forget to get the right belt
 
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