4.8 Liter Of Cola

iTrader: (1)

please post 'em. this is really interesting, and something that I'd like to do!

1slow01Z71

iTrader: (36)

Another vote for posting it up. I see you are in Houston check out the southern section we are always having get togethers about every 3ish months you should come out.

Ron's5.3

iTrader: (1)

Here is a write up of someone installing an Aux battery in a 2000 silverado. Wish I could remember where I downloaded to give them the credit. It goes into more detail about wiring for a camper, but has great pics and a brief explanation. This should work on up 2004's for sure. Tried to upload a .doc, but to large so cut and paste. At the bottom is some links for other things.

2000 CHEVY SILVERADO 6.0L AUXILIARY BATTERY INSTALLATION
OK, here's my battery story.

Chevy at first said you couldn't get the aux battery when you get California emissions (required here), then after I ordered the truck I learned they removed that restriction. So I ordered most of the parts from the parts department and did it myself. The details apply to a 99/00 Silverado. The parts you need:

15705102 Support bracket $12.85
356668 Battery clamp (group 78) $5.70
12135194 Relay $42.84
15321214 Cable, pos to relay $29.00
15321259 Cable, starter to relay $33.66
15321207 Cable, neg $30.35
21021808 Nut, metric, bag/10 $3.60
? Bolt for battery clamp

At minimum you should order the battery tray (support), and the starter to relay cable. You must order the support at least, It replaces an existing bracket. The other items can be bought in some form aftermarket but the factory items fit nicely and are well made. If desired, they sell a battery insulator jacket like is on the main battery for only a few dollars.

There is no group 78 (or any other) battery I've found that is short enough to fit under the existing corner brace that goes from the firewall to the fender/quarter panel above the battery location. Actually my Optima may fit if turned on its side but then the hold down wouldn't work. GM removes this brace if you order the aux battery option and so must we. However I'm told an Oddysey battery will fit under the brace. It's specs are HxLxW 5.8x7.05x6.7", 470CCA, $180. The down side is you have less power and have to make your own hold downs.

The overall concept is that the alternator output is taken from the heavy cable attached to the starter motor, run to a relay, and the other side of the relay then goes to the aux battery AND the camper. This means when the engine is on, the main battery and the aux battery and the camper are all connected together (in parallel) so the alternator can charge everything. Then when the ignition is off the relay opens up and only the aux battery is connected to the camper. If the camper has its own battery (mine does) then the two batteries are connected together so you get double capacity. Of course you can run them down without affecting the main truck battery.

Now some useful details I learned. First, disconnect the main battery negative cable!

Attach the cable to the starter using one of the new nuts, don't take off the original cable, just add the new one. The stud is long enough. Access the LOWER starter stud via the passenger side wheel well. I was able to reach over the top of the tire and get in there with a small ratchet. The end of the cable with heat shielding goes here.

Find the connector for the relay control hanging near the air conditioner dryer tank. This is near the aux battery location against the firewall. It is a 2 pin connector, if you don't have air cond. then there might be two connectors. The one with the white locking clip is for the air cond., use the other one. Mount the relay on the firewall in a convenient location, you have to drill 2 holes. Don't put it where the battery will hit it or where the studs could touch metal parts. Plug in the little connector and attach the heavy cable to the bottom stud using one of the new nuts. Tie the cable to the frame away from the exhaust manifold. Notice the cable has a fusible link in the relay end.

Get some heavy automotive wire, at least 10 gauge. Put a ring lug on one end and connect it to the top relay stud. This wire has to go across the engine bay to the big fuse box on the driver's side. I ran it up over above the engine using clamps to hold it to the firewall. The aux battery positive cable also attaches to the same relay stud.

I ordered the trailer towing package and the camper/5th wheel wiring options. These are both the same electrically but the camper wiring just has an extra bundle between the cab and bed with unfinished ends. The following details apply to both the camper and hitch wiring.

The camper positive lead is red and comes into the engine bay fuse box in one of those big covered bundles. It goes to a hidden stud and is powered via the upper left most fuse (40A) which isn't installed from the factory but they give you loose with the towing option. We don't use this because we don't want main battery power. To get this wire free, you need to lift the entire plastic body off the fuse box. Remove the top, then pull the bottom far side away from the little tabs locking it down. Pull up and you can get a few inches of movement. You may need to unlock the clip between the fuse box and the fender with a screwdriver. The cover will not come off due to a bracket but you can get enough distance to see the red wire on the stud in the far left corner. Remove the wire, pull it out and put the plastic back in place.

This is the feed for the camper and needs to connect to the heavy wire coming from the relay. You shouldn't connect them directly because it's a safety hazard. A better way is to connect them through a circuit breaker. At the auto or RV store they sell little 30A breakers for about $3 that have two studs. Connect each wire to a stud and you have a nice junction block and protection against shorts. I mounted the breaker on the plastic fuse box, in the cutout where your fingers go to pull the cover off. This way the connections are covered when the cover is on.

Only thing left is the aux battery negative cable. The factory connects it to somewhere on the upper rear of the engine, I couldn't find where. I connected mine to the engine block via the bolt securing the oil dipstick support bracket to the side of the block. Route or tie the wire to keep it away from hot things.

For the camper end, I ran the wire bundle into the bed through one of the existing drain holes in the front corner. To protect the wires I lined it with plastic edging first, a good wrap of electrical tape on the bundle would work too. Then ran it behind my bedliner and mounted a nice metal connector in the bedliner wall (had to shorten the connector with a hacksaw). I bought the connector at the RV store. It fits almost flush against the bedliner, has 6 pins and a spring loaded door to keep the elements out. The door also locks the mating connector in when inserted.

I put in a similar system in my old truck but didn't have any factory provisions to work with. I used a relay from the RV store ($17) and it worked fine, or you could use a solid state isolator. I learned that those relays can't tolerate water so be careful where you mount it if you go this way. I sealed the second one with RTV and never had a problem. Also be sure to use a circuit breaker or fuse between the between the aux battery and the camper, otherwise it's a fire hazard.

Factory Schematics

It seems that GM's system is to use the aux battery as a remote charger. The camper/trailer wiring draws from the primary battery so it may be too low to start the engine. Assuming it has enough juice to throw the aux relay, by placing the key in RUN and leaving it for a few minutes, the aux battery charges the primary. Then when you turn the key to START, the relay opens so starting current isn't drawn through the relay. A pretty stupid system. Just wire it so the camper draws off the aux battery and you will never have a dead primary. Also you can install a deep cycle battery for the camper which is where you need it.


Also, wrangler power products makes a dual battery kit for the silverado. Allows you to jump start yourself if needed. Here is link to an install.
http://www.off-road.com/chevy/reviews/wranglerdb/

Here is a link to a dual alt and battery install.
http://caraudiomag.com/technical/020...al_alternator/

After I complete mine, I will include a write up and pics. Hopefully within the next month.

Ron's5.3

iTrader: (1)

These are the pic's of my install so far. New Fuse block and terminals with 12 fuses & 8 Relays. The fuse block will be mounted above the A/c on the firewall. White Rodgers solenoid mounted on the tray. Going to have to swap the solenoid and the stud for clearance issues. The stud will give 12volt power to the front and back of the vehicle with anderson connectors, and be able to jump start myself. The one shows battery bracket mounted and a 9 conductor speed wire already ran to the inside above the overhead console for switches.

I am trying to plan for all my future electrical needs, so I will not ever have to rewire it. I finally have everything but the alt brackets. The hardest part was finding all the parts for the cheapest price from the web.

JimS

Nice thread. Thanks. Jim