how difficult to add a second battery?

[madmanjustice]

Would I also need to change out the alt for one from a PPV?

 

[Sparksalot]

It’s really just a battery hold down, plus two cables to put them in parallel. The negative cable is pretty short, the positive routes under the engine over to the starter. You’ll have two positive cables on the starter terminal. Going this route, the batteries must match, and be the same age.

most PPVs have a 160 amp alternator, so you might already have that.

 

[wsteele]

Would I also need to change out the alt for one from a PPV?

There are a few options on the how part. As @Sparksalot indicated you can run them in parallel, you can use an isolator so one would be your start battery and the other an accessory battery, etc. if you know what scenarios you want to address, there is a pretty simple install to accomplish it.

A quick YouTube search will produce many different videos of approaches that accomplish various goals.

 

[swathdiver]

Would I also need to change out the alt for one from a PPV?

Nope. @intheburbs

Bill has done an excellent tutorial on installing the TP2 auxiliary battery, I just don't remember where anymore.

 

[intheburbs]

I did it on both my GMT900 trucks. I basically used GM parts to create what would otherwise be the TP2 dual battery option.

Have had the setup for 7 years now in the Suburban, and 5 years with the Denali. No issues.

If you'll indulge me for a quick funny story - the primary started dying on the Denali. I was driving around town and we stopped at one point and were sitting with the engine off but radio on for about 30 minutes. Well, that was enough to kill the primary. Remote start wouldn't work either. Primary was so dead it wouldn't even energize the isolator. I pop the hood and get out, planning to use my jumper cables to use the secondary to jump the primary. Two separate guys stop and ask if I need a jump. I say, 'No thanks, I'm good. " And then several others walk up as they see me connecting both ends of the cables under my hood. Now I have an audience. I had no idea if this would work. I hoped, fingers crossed. Make the connections, get behind the wheel, "click." Damn. Get back out, wiggle the connections, get back in and try it again - starts right up! Jaws dropped at my magic. LoL

Here's the thread, including descriptions, pictures and parts list...

Aux Battery or TP2 upgrade - Chevrolet Forum - Chevy Enthusiasts Forums

Tahoe & Suburban DIY and Useful Threads - Aux Battery or TP2 upgrade - So I had been looking around for a guide to installing an OEM aux battery in my 2009 suburban, and I was not successful on finding an inclusive DIY. So last summer 8/2013, I pieced one together, borrowing from a few other...

chevroletforum.com

 

[Joseph Garcia]

I have 2 batteries, but not with an isolator or any related ancillary equipment. I have high amp connectors, whereby I can connect the second battery to the system, in parallel, whenever I want to. I periodically connect the second battery to the system, to keep it fully charged.

 

[N9Phil]

When you add two batteries in parallel you are only increasing the amperage capacity of your system. Both batteries should be the same size capacity so if you have two 60 amper hour batteries you now have equivalent to a 120 amper hour battery. You are only doubling the amper hour capacity of your system. I have done this for years on my Suburbans and my boats. Unless you have excessive current draw your current alternator should do the job.

 

[Tozan]

@madmanjustice I just did mine in parallel
Here is my post on doing it.. Dual Batteries installation It took about 20 minutes and I have been running it this way for over 3 years now.