Battery Replacement Question

First you need to determine which side is negative and which side is positive by looking at the top of the battery and grab a 9/16" or 14mm to remove and install the nuts on the top of the battery posts. Hopefully the tech left the wires in some reasonable order so putting the new batteries in you can follow where they are located, but if they didn't short of tracing the wires you're probably going to have a mess. Color code may be messed up on a truck that old, but in general if you have red wires they are positive and in terms of major wires ground is black, but some upfits may be different. What you really need is to get the starter hooked up though, so you don't need to worry so much about the upfitting right now. If your heavy gauge starter wires are both the same color and unmarked, the wire that comes from the solenoid, usually on top of the starter, is your positive and the one that comes from the front of the starter itself is your ground. Face all the batteries in the same direction so these wires fit properly. Install the small jumpers from battery to battery positive to positive to positive on one side and negative to negative to negative on the other side and tie your starter wires usually to the first battery (toward the front of the truck) by putting the positive wire on the positive post and ground wire to the negative post. You can probably determine the rest by the length of the wires if you're going to get into it at all. Like I said, if you have upfitting you may have to do a little more tracing to figure out all the high gauge (thin) wires, but in terms of getting the engine to crank, you don't really need your upfitting to work - just make sure if you don't hook something up you secure the wires away from the terminals. If it has a kill switch or something let me know. You can delete it for ease which is what I usually do if a truck is in real bad shape, but there are going to be extra low (thick) gauge wires in there so you'll have to do more sorting.

 

Nope.... Positive to Positive.... 4 batts.... 4 pos posts.... 2 heavy duty cables coming from starter...... pos to pos n connect one of the Starter cables.... Repeat....

 

Thats a lot of good information. Just needs some spacing.

 

just figured i would bump up the title

NAPA has 1100 CCA for $89
TA was $150

NAPA also had 4 post red and black cables, freighliner had them for almost twice as much

 

Here's a look at my setup. I want to say that the batteries are hooked up in series (but I'm no electrical expert). The main positive (huge cable) hooks from one of the terminals all the way to the starter solenoid (which sits on top of the starter). I haven't followed the path of the negative cable but I do know that a portion of it goes to ground (your frame is ground), which you can't readily see here. Just know that the negative cable takes two paths as it exits the battery compartment - one of them will be a short cable to ground. There is also a similar grounding cable from the starter to the frame.
View attachment 64122

 

Those with little to no working knowledge of electricity should beware, modern electronics will not tolerate many aberration ...

Basics,

Parallel: all the + connected together, all - connected together and to frame ground... This will supply 12.6dc, but the CCA will be a total of all battery cells..

Series: Pos to neg on next battery, Pos to Neg on next, ect: This configuration will provide a voltage equal to the sum of the batteries in the string ( 12.6+12.6= 25.2vdc), the CCA however will be the average (1100+900=1000)...

Note: some vehicles use 24 to start, 12 to run.. These applications require a bank of relays to switch source...

..... Philip

 

Lol thanks for the clarification RSQ20, I always get those two mixed up. You can call it whatever, if it works lol