CK5
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'89 R3500 Crew Cab 2wd to 4wd conversion & beyond

Started out with 2wd TBI350 with SM465 to current 4wd with 454, 700r4, NP241
Do you think one of those terminate yourself kits for the engine harness would have been a good idea?
It would still be more work, you have to terminate every single connector and wire. Now, if it was a show truck where you were trying to hide everything and make it look perfect, then it might be the correct solution. But to make it work reliably and look professional at least, I don't think that's the best option here.
 
Not seeing how the loom is taped and sealed, I would have explored the possibility to pull the fuel pressure wiring out of the loom closer to where you needed it.
 
Even for a ls it’s long, I think mine goes up to the alternator then looped back to the end of the rail.
 
Not seeing how the loom is taped and sealed, I would have explored the possibility to pull the fuel pressure wiring out of the loom closer to where you needed it.
I thought some about that but I felt like I'd be halfway down the rabbit hole @folkenheath and @Babaganoosh were talking about with the unterminated harness.

They used braided nylon wrap around loom and then taped all of the junctions with electrical tape. So it wouldn't be horribly difficult to re-loom but with my tendency to over-think, it would have taken a long time. :doah:

I also try to plan for the future a little considering my history of changing things. Like what if I ended up putting a 6.0L in, I'd have a ready harness for it. Or if I pull the whole thing to sell it, it's nice to be unmolested.

Speaking of a history of changing things I was recently observing all my various mounting holes that have been drilled into the firewall. For this recent work I had my pick of holes to use. :rotfl: Still gonna end up adding a few new ones! :doah:
 
I've been running a battery in the bed and another in the engine bay that I'm now going to be moving to the back also due to losing space for the narrowed front. I'm a little uncertain about how to ground the batteries.

Do I ground them both to the frame rail near the batteries and then ground the stuff in the engine bay to the frame as well?

Or would it be better to run cables from the batteries all the way to a bus bar in the engine bay? I could be a single cable, a shorter piece that connects the 2 batteries with a single longer cable that runs up to the engine bay. Both batteries would still have a ground to the frame as well.

Maybe the question boils down to this, will the frame carry as much current as a 4/0 battery cable?
 
I've been running a battery in the bed and another in the engine bay that I'm now going to be moving to the back also due to losing space for the narrowed front. I'm a little uncertain about how to ground the batteries.

Do I ground them both to the frame rail near the batteries and then ground the stuff in the engine bay to the frame as well?

Or would it be better to run cables from the batteries all the way to a bus bar in the engine bay? I could be a single cable, a shorter piece that connects the 2 batteries with a single longer cable that runs up to the engine bay. Both batteries would still have a ground to the frame as well.

Maybe the question boils down to this, will the frame carry as much current as a 4/0 battery cable?
I don't know the answer to that exactly but my big rig which has a big frame does have a dedicated ground cable to the starter.
I have been trying to have a good ground to the engine block or the starter on every vehicle, I also one to the frame and another to the tub.
I also have been putting 2 batteries in every vehicle
 
More is better, I would definitely run a dedicated one to the block/starter area as well as from block to body, frame to body etc....
 
I've been running a battery in the bed and another in the engine bay that I'm now going to be moving to the back also due to losing space for the narrowed front. I'm a little uncertain about how to ground the batteries.

Do I ground them both to the frame rail near the batteries and then ground the stuff in the engine bay to the frame as well?

Or would it be better to run cables from the batteries all the way to a bus bar in the engine bay? I could be a single cable, a shorter piece that connects the 2 batteries with a single longer cable that runs up to the engine bay. Both batteries would still have a ground to the frame as well.

Maybe the question boils down to this, will the frame carry as much current as a 4/0 battery cable?
Everything I move the battery to the back I use a solid, large, short ground to the frame, typically 1 or 2 AWG. Then another short ground from the frame to the engine block. The frame has a lot more metal to carry current than even a large cable. Two short cables and a huge frame are better than a long cable. The key is, the connections have to be solid, clean, and reliable. You have to grind the frame clean to metal and then if you want put the corrosion protection over the completed connection. Also, use the same side of the frame, don't use the right side of the frame in the back and the left side in the front, then your ground depends on the rivet connections. I use the right side since the battery is better off in the right rear. Then I connect all grounds to that side.

Of course, in addition to the two main ground cables, I also run a ground from the frame to the core support, and frame to firewall/cab, etc. I don't ground the cab to the block, just solidly ground the cab to the frame, you don't want to create ground loop issues. For example, if you ground the cab to the block, then everything in the cab would have to go through the electrically noisy engine block to get ground. It should skip the block and go to the frame. This is why with CnP each bank of coils has a dedicated ground for that cylinder head, to shorten the high voltage noise path from the ignition system to mainly one cylinder head. However, this reduces it, it doesn't eliminate it, which is why everything should ground to the frame.

Except the ECU, that has to go directly to the battery for the cleanest possible ground.
 
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Everything I move the battery to the back I use a solid, large, short ground to the frame, typically 1 or 2 AWG. Then another short ground from the frame to the engine block. The frame has a lot more metal to carry current than even a large cable. Two short cables and a huge frame are better than a long cable. The key is, the connections have to be solid, clean, and reliable. You have to grind the frame clean to metal and then if you want put the corrosion protection over the completed connection. Also, use the same side of the frame, don't use the right side of the frame in the back and the left side in the front, then your ground depends on the rivet connections. I use the right side since the battery is better off in the right rear. Then I connect all grounds to that side.

Of course, in addition to the two main ground cables, I also run a ground from the frame to the core support, and frame to firewall/cab, etc. I don't ground the cab to the block, just solidly ground the cab to the frame, you don't want to create ground loop issues. For example, if you ground the cab to the block, then everything in the cab would have to go through the electrically noisy engine block to get ground. It should skip the block and go to the frame. This is why with CnP each bank of coils has a dedicated ground for that cylinder head, to shorten the high voltage noise path from the ignition system to mainly one cylinder head. However, this reduces it, it doesn't eliminate it, which is why everything should ground to the frame.

Except the ECU, that has to go directly to the battery for the cleanest possible ground.
I ground from the batteries to engine, body, and frame.
All direct, all heavy gauge
 
Been covered very well here. You most certainly can use the frame, esp the aux battery. As said the connection to the frame is critical, I can't begin to tell you how many times a batch of new custom built trucks with equipment mount on the bed, think boom, crane, winches, lift gates, failed to function properly all because of a crappy frame ground. 1 instance a batch of 25 Freightliners with folding telescoping Effor crane, had a 5/16" bolt through a 3/8" frame hole and eyelet. Installed like the by Freightliner, all 25 painted and none tight. Might want to look your boom truck over, I bet the grounds could use some tlc.

Every connection adds resistance, even the best cleanest. Keeping the least amount of connection between your cranking battery and the starter can be the difference between a no crank and cranking right up on a hot soak type situation. The bell housing might be a good compromise for an engine ground.
 
I ground from the batteries to engine, body, and frame.
All direct, all heavy gauge
Although everything needs to be grounded, I try not to do that exactly, because then you add noise to the battery.

I typically ground straight to the engine block, and then ground from the block to the frame, and then ground everything else to the frame or sometimes the block in that case.

But with the battery in the back, I just ground straight to the frame, and everything else, except the ECU (if used), goes to the frame.

The creates the cleanest possible ground at the battery for the ECU to use, and a solid ground for everything else.
 
Semis do it both ways. Some run cables to the starter from the batteries for ground. Some run batteries to frame and frame to starter. I think any way works fine it's just a matter of how good your connections are and how much you want to spend on cables.
 
Semis do it both ways. Some run cables to the starter from the batteries for ground. Some run batteries to frame and frame to starter. I think any way works fine it's just a matter of how good your connections are and how much you want to spend on cables.
On my semi trucks the distance is such that it would have been the same length of cable either way, so I guess by doing cable direct they saved 2 connections and the hardware.
I agree if batteries were further it would make sense to do the frame
 
You guys have helped a lot. I felt like I was victim to some false concept that a frame was a good current carrier. I kept thinking I had read somewhere the frame didn't carry much current. Something about surface area of the frame versus all those strands of copper in the large cable. But then I kept thinking it seemed like the frame should be plenty good enough. As I mentioned, over thinking...

I think my plan is good then. I'll sketch it all out and post up so you all can see, but mostly I'll post it for future Scott that won't remember what I did.... I've searched back thru this thread several times in the process of this recent work trying to find what I did before. :doah:

You have to grind the frame clean to metal and then if you want put the corrosion protection over the completed connection.
I always clean/grind grounds anytime I have to touch them. I noticed pulling some off yesterday there was corrosion under the terminal on the frame and thought I need something to protect them. I found an aerosol spray can coating to spray over electrical connections. Anything in particular people would recommend?

The creates the cleanest possible ground at the battery for the ECU to use, and a solid ground for everything else.
The Terminator comes with a very long power/ground lead that I think will reach one of the batteries. Do you ever add to the leads? I'm assuming it would be a good case for soldered butt connections.
 
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