Alternator going? Thinking about 160 AMP PPV generator upgrade...

So the other day as I was driving my navigation unit suddenly turned off, my airbag light came on then a "service traction control" warning in the DIC appeared briefly. I peered over at the battery gauge and it was way below the usual 14v (Especially for a new battery less than a few months old) I opened up the Torque Pro app and my voltage was reading 11.8v before climbing back to 12.1v... normally it's sitting comfortably around 14.4 to 14.6v without much wavering now it's anywhere between 12.1 and 13.8 more often than not. I have a 2010 Avalanche with just over 100,000km and figure maybe its time to replace the alternator now that I've got a 1400W stereo system a massive light bar and a couple other additional work lights attached to it along with some future power equipment I'd like to run.

I heard the Tahoe PPV 160 AMP alternator works pretty great and bolts right up without any further modification necessary. I was wondering if I had to upgrade any my existing electrical system in order to use it? I eventually plan to do the big 3 but more immediately would like to at least drop in a new generator to get going. I was given the GM part number 25877026 for $402.06 CAD. I went to GM Parts Depot Canada and its telling me the part number is for a re-manufactured alternator. If anybody can confirm if that is the correct P/N i'm pretty much ready to pull the trigger here and buy one unless my electrical system is fine and should be looking at another problem here...

That is the part number I get too, tell them you want a new one.

You can find bigger ones for cheaper on Amazon. Just make sure they are reputable manufacturers... I am keeping my eye on a 250amp that is under $200 USD... Think it was one MS03 2500 posted a while back...

If truly 1400 watts you are pulling over 116 amps just with your stereo system when everything is "hitting" at max assuming 100% efficiency in the amplifiers and that you were pulling max volume out of the amplifiers... In reality if you have an older style AB Amplifier they were only 50% efficient so you may be pulling over 200 amps from the stereo. (Newer D amplifiers are much more efficient but still not near 100% otherwise they wouldn't make any heat at all)

Add in light bars etc...

Figure  Wattage / Volts = Amps.

I suspect if you add up everything you can run full on you might find even a 250 amp alternator is too small. Note that if you DO pull more than the alternator can pull the battery will make up some for a little while but you can burn up your alternator. It is best to size the alternator for what you can do with everything full on.

But again, it will depend on the accuracy of the rating on the items you are running. If you are using decent equipment that is rated realistically you could easily find out you need well over 300 amps to properly run all of your equipment...

Rodney

How many amps does a stock Avalanche pull when driving, A/C on, headlights and the fan going?  I'd just like to calculate the kind of total load to better choose a proper alternator.

Actually quite a bit, when I added a Nav to my 03 at night with the AC on every time the compressor came on the headlights noticeable dimmed and the engine studered.

Now I went from a 105 to a 145, but I'm going with electric fans and up it to a 250.
Just be aware if you go past say 180 you have to modify the wiring with a Big 3 kit.

Find out what your truck has stock, Likely 105... Start there.

If you have things like heated seats and power sunroof you may want to figure on starting at 130 amp unless your truck came with a bigger alternator. I BELIEVE the police package has the 145 amp alternator but not 100% sure. There may be other combos that got the bigger alternator as well.

Another option is to look in your area for an alternator re-builder. They may be able to take your stock alternator and put different guts in it to make it a 300-400+ amp alternator for a reasonable price.

If you truly are running that large a system you will need a much bigger alternator than you are currently planning for or you will just burn them up.

To properly wire your truck and not get real crazy with the wiring you will want to run power and ground directly from your battery to the after market components.

This will allow you to only need to replace the battery to block ground and the alternator to battery positive. The rest of your power and ground wires will be sufficient to run factory equipment.

Also make sure to use either fuses or circuit breakers within 18" of a power source for each wire. (Mainly from the battery to components... )  While you CAN fuse the connection from your alternator be aware that you can blow your alternator and/or cause serious spikes in your system if a battery is not connected to the alternator. Today's systems require a battery to smooth out the alternators output.

Good luck!

No such thing as too large an alternator, or too large of wiring... But too small of either is a bad thing.

Rodney

Samsquanch said:

I heard the Tahoe PPV 160 AMP alternator works pretty great and bolts right up without any further modification necessary. I was wondering if I had to upgrade any my existing electrical system in order to use it? I eventually plan to do the big 3 but more immediately would like to at least drop in a new generator to get going. I was given the GM part number 25877026 for $402.06 CAD.

Click to expand...

Any alt in a DR 44 case will be a direct bolt on. If you want direct plug and play, you'll need a 2 pin connector.
$402.06 is crazy talk for a 160
You can pick up a reman 160 for under $150 U.S.  https://www.amazon.com/gp/product/B0031HXZLA/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1
If you want certified power you can look at nations or mechman. You can get a new 165A from nations for $190US. they have a little lower output @ idle, but are very strong for the price, I now run a nations 200 and 220 side by side.(twin charging systems)
http://nationsstarteralternator.commerce-search.net/nav?Year=2011&Make=Chevrolet&Model=Avalanche&Engine=5.3L+V8
Mechman units are known for their high output at idle and are one of the go to alternator manufactures in the competition 12V audio scene. They are more expensive, but are certified and have high idle output. A plug and play 240A will set you back $350 U.S

Samsquanch said:

How many amps does a stock Avalanche pull when driving, A/C on, headlights and the fan going?  I'd just like to calculate the kind of total load to better choose a proper alternator.

Click to expand...

When starting my build, we tested draws on the stock electrical system between 91 and 96A, w/ simulated peak draws, like high beams on and holding all 4 window switches up even though the windows were closed, a/c and fan on (basically doing everything we could to load the system as much as possible), the highest draw we saw was 100.63A

I had no idea the factory generator was as under-powered as it was.  Looks like it was designed to meet the minimum output possible to make the truck run.  Here in Canada buying a Mechman is going to be a very pricey adventure with the exchange rate, shipping costs and duties.  By the time a 270A Mechman gets to me it'll be about $700 CAD, but I think it's the kind of the price I'll have to pay for the kind of reliability and output that I'll need.

Calicak89 said:

Any alt in a DR 44 case will be a direct bolt on. If you want direct plug and play, you'll need a 2 pin connector.
$402.06 is crazy talk for a 160
You can pick up a reman 160 for under $150 U.S.  https://www.amazon.com/gp/product/B0031HXZLA/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1
If you want certified power you can look at nations or mechman. You can get a new 165A from nations for $190US. they have a little lower output @ idle, but are very strong for the price, I now run a nations 200 and 220 side by side.(twin charging systems)
http://nationsstarteralternator.commerce-search.net/nav?Year=2011&Make=Chevrolet&Model=Avalanche&Engine=5.3L+V8
Mechman units are known for their high output at idle and are one of the go to alternator manufactures in the competition 12V audio scene. They are more expensive, but are certified and have high idle output. A plug and play 240A will set you back $350 U.SWhen starting my build, we tested draws on the stock electrical system between 91 and 96A, w/ simulated peak draws, like high beams on and holding all 4 window switches up even though the windows were closed, a/c and fan on (basically doing everything we could to load the system as much as possible), the highest draw we saw was 100.63A

Click to expand...

BTW when GM started using electric cooling fans in 2005 they upped the output to a 145 amp so with a 160 amp you are only getting a additional 15 amps.

Samsquanch said:

I had no idea the factory generator was as under-powered as it was.  Looks like it was designed to meet the minimum output possible to make the truck run.  Here in Canada buying a Mechman is going to be a very pricey adventure with the exchange rate, shipping costs and duties.  By the time a 270A Mechman gets to me it'll be about $700 CAD, but I think it's the kind of the price I'll have to pay for the kind of reliability and output that I'll need.

Click to expand...

That sucks on the duty taxes.
The stock unit should be a 145, not terribly underpowered, there is some room there for accessories.
Could you order a Nations, Mechman or DC unit into one into a shop or distributor in Grand Forks and make the drive down? A 4 hr. round trip might be worth a couple hundred in savings.

Also might still be worth looking into a Canadian company that can redo your alternator. Rewinding your alternator for more power might be much more efficient for you in the long run.

Another option is like Calicak89 said... If you have friends in the US or can find someone to help you out you could drive down, get a new alternator, install it and drive back leaving the old alternator for scrap or whatever.