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So im looking to do an alternator upgrade to the big 160 amp 2001-2006 Dodge Durango 4.7L V8 alternator in my 98 Cherokee. It may be a bit over kill for what I have but go big or go home right? I plan on getting the Big 7 kit in 2GA from https://www.jeepcables.com/shop/xj-b...lete-kit-y5eg5 to go along with it. I have also purchased a brand new battery as this jeep has been a battery MURDERER. I think since we got it around 7-8 years ago it has always killed the battery over night. I finally did a parasitic draw test and found that the under hood light which has never worked was causing the the draw even though the bulb was shattered. Its been an electrical nightmare since day 1. Recently I have been coming out of work to a dead battery again and I have noticed once I jump it, the voltage drops to 9 volts, with some gas will then climb to above 14 volts and if I turn on my heat that some what works it will drop to 9 again and if its at 14 and I step on the brakes I notice all interior lights dim but I can usually just let it sit at idle and after about 20 minutes when I would leave it would be fine. The other day when I tried this I came back about 15 minutes later and it was shut off. It was friday and I wanted to get home after a long shift so I jumped it and as I was driving the gauge kept dropping to 9 randomly and every time it did there was this awful screeching sound which only occurred from stopped at idle all the way to 4th gear and I could usually get it to stop after shifting a few times. But this screech is not new, it has always happened when I started the jeep and I assumed it was the power steering pulley because if I turned my wheel without moving, it would become slightly louder. My belt is tight and I have replaced it twice just to make sure. Im hoping this upgrade will fix that but I want to make sure im not missing anything. I have read this forum https://www.cherokeeforum.com/f67/19...ctures-179443/ which is extremely helpful for anyone looking to do this upgrade. And if this doesnt fix my dead battery or horrible electrical problem whats next?
I took a different route. Grabbed an alternator for an '00 out of the boneyard, had a guy rebuild it, and he was able to get the amps to just shy of 155.
It will be a straight bolt in.
I decided to make my own battery cables. Used the Harbor Freight crimper. To be frank I probably spent what you are going to spend at that link for battery cables. All 2 gauge.
Also I decided that I want to fine tune some things. I used 45 degree and 90 degree lugs in various places.
And instead of using the mega fuse in the holder I put it in front of my PDC. Like to claim credit for that idea but I just stole it from other guys. LOL.
While it was a little time consuming I am pretty happy with how it came out. And how the Harbor Freight crimper performed too.
Couple shots.
Assuming you solved the parasitic draw issue with the under hood light, it sounds like a solid plan to me. I've always wished I did 2 AWG instead of 4 AWG when I did my alternator upgrade way back.
I agree with above. Ensure you have solved the pre-existing issues before upgrading. If your belt truly is tensioned correctly and you're getting belt squeal accompanied with voltage drop its possible the pulley on the alternator is seized/seizing.
Assuming you solved the parasitic draw issue with the under hood light, it sounds like a solid plan to me. I've always wished I did 2 AWG instead of 4 AWG when I did my alternator upgrade way back.
I kinda wonder if that is overplayed a bit. The general consensus seems to be up to 150 amp 4 gauge is fine and anything over that you should 2 gauge.
My guy who did my alternator was not sure where he would end up. I told him I need to know so I could use the appropriate gauge.
He said 4 gauge would be fine.
My logic was everybody says what they say about what gauge to use, 2 gauge over 4 gauge cost me an extra 15 cents/foot, and isn't bigger always better? LOL.
But then again if your running dual batteries, winch, etc, etc then yeah it probably does matter so much more.
Several things.
1. Check the all the idler pulleys in the belt path and make sure there are no seized bearings, you mentioned replacing the belt a couple of times, something is wearing the belt.
2. Assuming the alternator bearings are not seized and the alt is spinning normally, a weak charge could be caused by bad diodes inside the alternator.
3. 4 gauge wire is more than sufficient for the charge wire off the alternator. On my track car I run a 200amp alt with a 6 gauge charge wire. The only place I run 2 gauge is between the battery and starter solenoid and the battery and ground. Even a high output alternator will only generate what is required to recharge the battery plus power the system electrical load. In other words, just because you have a 150amp alternator does not mean it outputs 150amp all the time.
4. Install a good quality AGM battery. I use Odyssey batteries exclusively.
Last edited by Steve Hayes; Feb 15, 2020 at 05:15 PM.
I kinda wonder if that is overplayed a bit. The general consensus seems to be up to 150 amp 4 gauge is fine and anything over that you should 2 gauge.
My guy who did my alternator was not sure where he would end up. I told him I need to know so I could use the appropriate gauge.
He said 4 gauge would be fine.
My logic was everybody says what they say about what gauge to use, 2 gauge over 4 gauge cost me an extra 15 cents/foot, and isn't bigger always better? LOL.
But then again if your running dual batteries, winch, etc, etc then yeah it probably does matter so much more.
You know, in all honestly, it probably is overplayed. Having an intuitive physical understanding of amperage through a wire is damn near impossible without doing testing to see what it takes to melt wires. I'd feel better knowing that the wiring is overkill vs slightly on the small side. I did 4 awg with a 150 A fuse, which I feel is more than adequate. Stepping up to a 175 A or 200 A fuse, I'd want some beefier wires in there. That's some lowwwww resistance and those wires will flow some current. I want to be sure that fuse is gonna pop well before things go astray. I also have tentative plans to setup dual batteries. With the longer cables runs all around the engine bay I definitely think 2 awg is appropriate in the 175 A range.
I just recently relocated my winch solenoid to under my hood. The winch had 2 awg wires on it but I moved up to 1/0 awg. Talk about beef. Overkill? Likely, but I feel better knowing that the momentary 450 A the winch is rated to pull will have no issue flowing through there.
Originally Posted by Steve Hayes
On my track car I run a 200amp alt with a 6 gauge charge wire. The only place I run 2 gauge is between the battery and starter solenoid and the battery and ground.
What is that 6 awg wire fused at? The concern is not so much the actual current the wire is flowing, but ensuring the fuse will pop before the wire starts to melt. I wouldn't feel comfortable with more than a couple feet of 6 awg fused at 200 A.
IMO it doesn't make sense to have different sized wires downstream of the same fuse.
You know, in all honestly, it probably is overplayed. Having an intuitive physical understanding of amperage through a wire is damn near impossible without doing testing to see what it takes to melt wires. I'd feel better knowing that the wiring is overkill vs slightly on the small side. I did 4 awg with a 150 A fuse, which I feel is more than adequate. Stepping up to a 175 A or 200 A fuse, I'd want some beefier wires in there. That's some lowwwww resistance and those wires will flow some current. I want to be sure that fuse is gonna pop well before things go astray. I also have tentative plans to setup dual batteries. With the longer cables runs all around the engine bay I definitely think 2 awg is appropriate in the 175 A range.
With what you are doing I think the overkill is warrantied.
And that is another thing that you brought up. I am pretty clueless when it comes to auto electrical. So since it seems bigger can't hurt I just go with bigger.
Better safe then sorry. LOL.
Right now I still have my stock alternator in. Running a 125 amp mega fuse. I wanted to run with the new cables for awhile to make sure everything is OK.
When I put in the 155 amp alternator I will be using a 175 amp mega fuse.
Also going with the bigger is better, or can't hurt, theory I need to set up a central location for a bunch of relays.
Now I don't want to buy pigtails relay holders for them. I want to make them. I want 1 continuous wire. Would soldering extra wire to a pigtail be a problem? Probably not but still want to avoid it wherever possible.
I am leaning towards these for the relays.
The terminals they use will supposedly will accommodate 10/12 gauge wire. Which not all will. If you can find the specs on things like this,
and you would be surprised how many don't tell you in the description, they usually say 16 maybe 14 gauge. IMO while most likely adequate
still something they should tell you.
It occurred to me that when I said I was running a 6 gage charge wire on my track car I'm also not running a winch, so with that in mind I think the 4 gage is probably a better choice for your application.
Alternator upgrade
