Adding Dual Alternators for High draw inverter

[EZTundra77]

I'm interested in adding a second alternator and a second battery to my '17 L96 6.0 3500.  Theres a second spot for the battery.  I want a 225-250 amp alternator minimum.  And I would love to not void warranty if possible.  Any body have a specific alternator to look at.  I know there are different size pulleys.  I want to hook up a 2500 W inverter and it draws way mor amp than my HD 150 amp unit can deliver.  I would use a deep cycle battery as my second battery.  I already did the big 3 upgrade using 0 gwg tinned OFC so that wiil  help.  Any suggestions welcome.  

 

Thanks y'all and happy wheelin.

[redwngr]

Do you think the 220A alternator available on 6.0 (and included on 6.0 snowplow prep) would do the job you need done?

 

Factory duals was available on dmax only and paired the 150A with a 220A. 

 

 

Alternators

 

Standard --  KG4    Alternator, 150 amps

 

KW5         Alternator, 220 amps
1 - Included with (VYU) Snow Plow Prep Package when ordered with gas or diesel engines.

 

KHB         Alternators, dual, 150 amps and 220 amps each
1 - Requires (L5P) Duramax 6.6L Turbo-Diesel V8 engine.

 

Batteries:

 

Standard --    Battery, heavy-duty 720 cold-cranking amps/80 Amp-hr, maintenance-free with rundown protection and retained accessory power 

 

Dmax --     Battery, heavy-duty dual 730 cold-cranking amps/70 Amp-hr, maintenance-free with rundown protection and retained accessory power
1 - Included and only available with (L5P) Duramax 6.6L Turbo-Diesel V8 engine.

 

Auxiliary -- K4B         Battery, 730 cold-cranking amps, auxiliary
1 - Not available with (L5P) Duramax 6.6L Turbo-Diesel V8 engine or (LC8) 6.0L V8 SFI Gaseous CNG/LPG capable engine.

 

[EZTundra77]

4 hours ago, redwngr said:

Do you think the 220A alternator available on 6.0 (and included on 6.0 snowplow prep) would do the job you need done?

 

Factory duals was available on dmax only and paired the 150A with a 220A. 

 

 

Alternators

 

Standard --  KG4    Alternator, 150 amps

 

KW5         Alternator, 220 amps
1 - Included with (VYU) Snow Plow Prep Package when ordered with gas or diesel engines.

 

KHB         Alternators, dual, 150 amps and 220 amps each
1 - Requires (L5P) Duramax 6.6L Turbo-Diesel V8 engine.

 

Batteries:

 

Standard --    Battery, heavy-duty 720 cold-cranking amps/80 Amp-hr, maintenance-free with rundown protection and retained accessory power 

 

Dmax --     Battery, heavy-duty dual 730 cold-cranking amps/70 Amp-hr, maintenance-free with rundown protection and retained accessory power
1 - Included and only available with (L5P) Duramax 6.6L Turbo-Diesel V8 engine.

 

Auxiliary -- K4B         Battery, 730 cold-cranking amps, auxiliary
1 - Not available with (L5P) Duramax 6.6L Turbo-Diesel V8 engine or (LC8) 6.0L V8 SFI Gaseous CNG/LPG capable engine.

 

Good info.  I don't think 220 amp will cover it.  Adding another battery would be easy in to hook up but would likely overtax the alternator.  If I use an aftermarket aux battery and aux alternator, I wonder what exactly that could void in warranty.  Certainly charging system components I would guess.  It says the K4B isnt available on the LC8 6.0.  What about my L96 6.0?

 

[redwngr]

1 hour ago, EZTundra77 said:

Good info.  I don't think 220 amp will cover it.  Adding another battery would be easy in to hook up but would likely overtax the alternator.  If I use an aftermarket aux battery and aux alternator, I wonder what exactly that could void in warranty.  Certainly charging system components I would guess.  It says the K4B isnt available on the LC8 6.0.  What about my L96 6.0?

 

I believe it's just the natural gas / propane capable version that it's not available on. 

(RPO K4B code not on dmax, because it already has the 2nd battery in the spot for the aux battery)

I expect auxiliary battery can be added through parts/accessories

 

How long does the application need to maintain the high draw level? 

When stationary or on highway? 

 

T

[EZTundra77]

41 minutes ago, redwngr said:

I believe it's just the natural gas / propane capable version that it's not available on. 

(RPO K4B code not on dmax, because it already has the 2nd battery in the spot for the aux battery)

I expect auxiliary battery can be added through parts/accessories.  

 

How long does the application need to maintain the high draw level? 

When stationary or on highway? 

 

T

Only when stationary.  It would replace a jobsite generator to run an inverter which could run a 22 ton electric log splitter on occasion, supplement a solar battery bank, power multiple tools on a job site, etc.  I would like to run this as the aux battery: https://www.batterymart.com/p-odyssey-pc2150t-battery.html?gclid=Cj0KCQjwtMvlBRDmARIsAEoQ8zS2GLx1gIvpepBJ4gjstuM3DMJNI0HpHOcp1M7sLUpkZCcifijFLTwaAu55EALw_wcB

 

[EZTundra77]

The inverter from the log splitter needs 100 amps at least from the alternator.  It's 2400 w constant with peak draws near 3400 w.  

[redwngr]

Sounds to me like a Honda generator is a better solution.

 

https://powerequipment.honda.com/generators

[GTBensley]

I agree that a Honda generator may be a cheaper and better idea, plus you wont be adding the hours up on your truck while running it.

 

If you do go for the inverter, see if GM can program you for a high idle (yes its available on the 6.0 gas). Its a build option on the website to have it programmed into the vehicle, but I see no reason why they couldnt flash it onto the truck for you.  

[avalonandl]

Yes, a genset. The amps you are throwing around are MORE than I would feel comfortable running through vehicle wiring.

[EZTundra77]

2 hours ago, avalonandl said:

Yes, a genset. The amps you are throwing around are MORE than I would feel comfortable running through vehicle wiring.

I think you are right. I will go with a generator.  But I have ran 3000w RMS through a vehicle with dual amps, dual batteries, and the big 3 upgrade. I have the big 3 in my current truck using 0 gwg. OFC but it still seems questionable. 

[EZTundra77]

Ok. If I stick to the stock alternator, what’s a safe draw from an inverter?  1000w? 

[calsdad]

Sorry for reviving a thread from the dead,  but there was some good info in this thread and I was wondering if some of the people who responded might know the answer to my questions.

 

I have a 2010 Yukon XL 2500 (L96 6.0L gas engine) - and what I would like to do is add both a second battery , preferably isolated and just used to run accessories ( I would use a deep cycle) - and also add a high amp alternator.  I checked the build sheet in my glovebox and it looks like I've got the KG3 145 amp unit (from the list in this thread:  https://www.silveradosierra.com/electrical/which-alternator-do-i-have-t17960.html ) .

 

I've exchanged a few emails with tech support at Mechman - asking them if I could use one of their high-amp alternators with an isolator and they said that was a very bad idea because if the 2nd battery got heavily discharged it would potentially burn out the alternator as the alternator is not made for reviving heavily discharged batteries.  I also asked them if using a DC to DC charger would be a better choice - and they said that also would likely lead to issues.

 

So it seems like Mechman only really recommends 2 batteries in parallel - not an "isolated" battery. 

 

I checked my truck - and it does not appear to have a "smart" alternator.  Starting the truck up what I see is the initial charge is in the 14.5V range - and after a minute or two it settles down to 13.85 - 13.88V (with no load) - and stays there.

 

I was unaware of the KW5 220 amp alternator option from the later year trucks - so that might be an option for me as well.

 

But what I'm really looking to do is figure out how to best add that 2nd battery - isolated,  and the hi-amp alternator and have them work together properly.

 

The isolator and DC to DC charger units I've been looking at are the ones from RedArc

[RyF]

On 6/29/2019 at 6:34 AM, calsdad said:

Sorry for reviving a thread from the dead,  but there was some good info in this thread and I was wondering if some of the people who responded might know the answer to my questions.

 

I have a 2010 Yukon XL 2500 (L96 6.0L gas engine) - and what I would like to do is add both a second battery , preferably isolated and just used to run accessories ( I would use a deep cycle) - and also add a high amp alternator.  I checked the build sheet in my glovebox and it looks like I've got the KG3 145 amp unit (from the list in this thread:  https://www.silveradosierra.com/electrical/which-alternator-do-i-have-t17960.html ) .

 

I've exchanged a few emails with tech support at Mechman - asking them if I could use one of their high-amp alternators with an isolator and they said that was a very bad idea because if the 2nd battery got heavily discharged it would potentially burn out the alternator as the alternator is not made for reviving heavily discharged batteries.  I also asked them if using a DC to DC charger would be a better choice - and they said that also would likely lead to issues.

 

So it seems like Mechman only really recommends 2 batteries in parallel - not an "isolated" battery. 

 

I checked my truck - and it does not appear to have a "smart" alternator.  Starting the truck up what I see is the initial charge is in the 14.5V range - and after a minute or two it settles down to 13.85 - 13.88V (with no load) - and stays there.

 

I was unaware of the KW5 220 amp alternator option from the later year trucks - so that might be an option for me as well.

 

But what I'm really looking to do is figure out how to best add that 2nd battery - isolated,  and the hi-amp alternator and have them work together properly.

 

The isolator and DC to DC charger units I've been looking at are the ones from RedArc

 

I researched this project a lot longer than it took me to actually complete the upgrade. I wanted to make absolutely sure I didn't screw anything up with the computer when I did this. Now that it's done, and I've had the opportunity to run it this summer, I highly recommend the second battery wired up like this for the 6.0. I had some initial concerns afterward, but there's been no issue since I made this upgrade. There a lot of guys smarter than I am who commented within my post. There's some very good information in there thanks to them. I like that it looks fairly stock. I should theoretically never need another jump either. 

....I'm also considering adding the KW5 220 amp now. 

[calsdad]

10 hours ago, RyF said:

 

I researched this project a lot longer than it took me to actually complete the upgrade. I wanted to make absolutely sure I didn't screw anything up with the computer when I did this. Now that it's done, and I've had the opportunity to run it this summer, I highly recommend the second battery wired up like this for the 6.0. I had some initial concerns afterward, but there's been no issue since I made this upgrade. There a lot of guys smarter than I am who commented within my post. There's some very good information in there thanks to them. I like that it looks fairly stock. I should theoretically never need another jump either. 

....I'm also considering adding the KW5 220 amp now. 

  Thanks!

 

I'm going to go read thru your thread and see what you did.