Right battery issues
Lead Driver
Joined: Feb 2022
Posts: 7,955
Likes: 4,039
Disconnect the passenger battery and try to start it with just the drivers side. If it is not starting, the problem is a bad cable. The drivers side is getting charged, but the passenger side is wearing down by not getting charged. IIRC the charging system starts at the drivers side while the starting is on the passenger side.
I had a diagram, but wont load. Basically both batteries are wired together, so if one goes bad, the other should be able to start the truck, however it also holds true that if one goes bad, they both go bad. You may have something as simple as a weak crimp on one of the battery cables, more than likely the positive side as that will split the batteries.
I had a diagram, but wont load. Basically both batteries are wired together, so if one goes bad, the other should be able to start the truck, however it also holds true that if one goes bad, they both go bad. You may have something as simple as a weak crimp on one of the battery cables, more than likely the positive side as that will split the batteries.
Thread Starter
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Trailering
Joined: Sep 2012
Posts: 21
Likes: 6
From: Warren, Ohio
Disconnect the passenger battery and try to start it with just the drivers side. If it is not starting, the problem is a bad cable. The drivers side is getting charged, but the passenger side is wearing down by not getting charged. IIRC the charging system starts at the drivers side while the starting is on the passenger side.
I had a diagram, but wont load. Basically both batteries are wired together, so if one goes bad, the other should be able to start the truck, however it also holds true that if one goes bad, they both go bad. You may have something as simple as a weak crimp on one of the battery cables, more than likely the positive side as that will split the batteries.
I had a diagram, but wont load. Basically both batteries are wired together, so if one goes bad, the other should be able to start the truck, however it also holds true that if one goes bad, they both go bad. You may have something as simple as a weak crimp on one of the battery cables, more than likely the positive side as that will split the batteries.
Lead Driver
Joined: Feb 2022
Posts: 7,955
Likes: 4,039
Thats a good test, You should be seeing same voltages on both batteries. A lower voltage on the left battery (passenger) would be a good indication of a bad cable.
FTE Leadership Emeritus
Joined: Sep 2003
Posts: 12,241
Likes: 755
From: Houston, Texas
+1 on AGM batteries
I run the expensive X2 batteries on my 7.3 with a 230 amp alternator and they have yet to quit.
I've also noticed this on most 6.7's I've worked on. The most recent was a 2022 that was a little over two years old. The passenger battery was boiling over when he brought it to me. Makes me want to go pay him a visit and do some testing.
As suggested, I would check the continuity between the passenger battery and the alternator. There has to be a flaw somewhere causing this.
I run the expensive X2 batteries on my 7.3 with a 230 amp alternator and they have yet to quit.
I've also noticed this on most 6.7's I've worked on. The most recent was a 2022 that was a little over two years old. The passenger battery was boiling over when he brought it to me. Makes me want to go pay him a visit and do some testing.
As suggested, I would check the continuity between the passenger battery and the alternator. There has to be a flaw somewhere causing this.
Thread Starter
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Trailering
Joined: Sep 2012
Posts: 21
Likes: 6
From: Warren, Ohio
Definitely a flaw somewhere. The Interstate battery had boiled over causing it to fail. This Napa battery is a sealed unit so I haven't noticed anything from it. This is the reason for this thread, I was wondering if anyone else experienced this and if there was any fix. I'm getting some good information, hopefully I can get to the bottom of it with help from everyone here.
Hotshot
Joined: Oct 2015
Posts: 19,681
Likes: 12,803
From: Wyoming
Resting voltage is not a good indication of an effective system. Bad connections look just fine on the volt meter when there is no load. Add a load and you may find that the voltages look different.
I'm not sure how easy this would be but if you check the resistance to each battery, it may give you a better idea if there is a connection/cable problem.
On my LiFePO4 batteries that I build, I check the resistance for each cell before putting a battery in use.
I'm not sure how easy this would be but if you check the resistance to each battery, it may give you a better idea if there is a connection/cable problem.
On my LiFePO4 batteries that I build, I check the resistance for each cell before putting a battery in use.
Cargo Master
Joined: Feb 2015
Posts: 2,338
Likes: 255
From: Livermore Ca.
AGM batteries are expensive and last no longer than regular batteries. I like to buy Motorcraft batteries. I have had good luck swith the replacement ones. Go figure. I had a original one leak and replaced it with another one from the dealer. I replace mine every 6 years because they are supposed to last 5. My thought if the truck still starts fine than I can squeeze a little more out of them. But the first sign of crossion or sweating I dump them. Feel the side of your batteries if you feel a slight bulge than they are being overcharged. Sides need to be flat.
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Lead Driver
Joined: Jan 2002
Posts: 8,624
Likes: 4,709
From: Itinerant
Try rest voltage as a set then disconnect one at a time and get individual voltages.
Then try starting vehicle everything off. Same thing get voltages then disconnect one at a time get voltages.
Then turn everything on ( AC max, high beams , radio ...everything) and if you have something that can be plugged into the inverter to give more load draw. Then again check individual batteries then disconnect one at a time to get voltages.
See if something looks odd. I would think it's going to show on the battery that dieing early. It's a hands on troubleshooting way.
FTE Leadership Emeritus
Joined: Sep 2003
Posts: 12,241
Likes: 755
From: Houston, Texas
Originally Posted by The Bone
AGM batteries are expensive and last no longer than regular batteries. I like to buy Motorcraft batteries. I have had good luck swith the replacement ones. Go figure. I had a original one leak and replaced it with another one from the dealer. I replace mine every 6 years because they are supposed to last 5. My thought if the truck still starts fine than I can squeeze a little more out of them. But the first sign of crossion or sweating I dump them. Feel the side of your batteries if you feel a slight bulge than they are being overcharged. Sides need to be flat.
The advantage with AGM batteries is that they handle the heat better than the flooded batteries. Here in Texas, without fail, I have quite a few customers that find out they have bad batteries once the temps get to the mid 90's to 100+. Battery blankets that come from the factory on most Ford vehicles don't help either. The ones that manage to survive the summer meet their end when it starts to get cold. This is why top off and test the battery as well as the charging system on every vehicle I touch.
I'll dig into the charging system on a 6.7 and see what I can come up with. I'm working on a 2018 with a dual alternator and so I have a test subject.
Lead Driver
Joined: Feb 2022
Posts: 7,955
Likes: 4,039
A boiling battery is an overcharge condition. Sounds like you need to have the charging system inspected. It is possible the drivers battery is loose and not getting 100% throughput so the passenger battery is doing all the work. If you mentioned it earlier, I must have missed it. Either way I would inspect the drivers side cables and connections, the passenger side appears to be overworked.
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Trailering
Joined: Sep 2012
Posts: 21
Likes: 6
From: Warren, Ohio
This is not the first mention of cables, maybe it was another one of your comments. Since this truck has dual alternators, would that have any bearing on this situation? If there's an issue with the cables, it is right from the factory. I'm not saying it's not possible, we know how good factory can be and how badly they can fail.
Lead Driver
Joined: Jan 2002
Posts: 8,624
Likes: 4,709
From: Itinerant
This is not the first mention of cables, maybe it was another one of your comments. Since this truck has dual alternators, would that have any bearing on this situation? If there's an issue with the cables, it is right from the factory. I'm not saying it's not possible, we know how good factory can be and how badly they can fail.
Lead Driver
Joined: Feb 2022
Posts: 7,955
Likes: 4,039
I don't know if there is much difference between 20 ( i think you said 20) and the 24. The battery monitoring hardware in on the passenger battery on mine, only plain cables on the other side. Both batteries would be hard grounded to the chassis, and the positive cable should route from one battery to the other directly. If I read it right, then your issue was a boiled out passenger battery and no start with a known good battery on the drivers side.
Yeah need a load tester and alternator test done. I don't think it's a battery issue, but a charging issue which is leading to battery failure.
Yeah need a load tester and alternator test done. I don't think it's a battery issue, but a charging issue which is leading to battery failure.
FTE Legend
Joined: Mar 2017
Posts: 31,775
Likes: 9,113
From: Western NY
It depends on who's AGM battery you buy. If you spend the money on X2 batteries, you won't be disappointed. Walmart, O'Reilly, and other parts store batteries aren't built to the same standards as X2 and Odessy batteries.
The advantage with AGM batteries is that they handle the heat better than the flooded batteries. Here in Texas, without fail, I have quite a few customers that find out they have bad batteries once the temps get to the mid 90's to 100+. Battery blankets that come from the factory on most Ford vehicles don't help either. The ones that manage to survive the summer meet their end when it starts to get cold. This is why top off and test the battery as well as the charging system on every vehicle I touch.
I'll dig into the charging system on a 6.7 and see what I can come up with. I'm working on a 2018 with a dual alternator and so I have a test subject.
The advantage with AGM batteries is that they handle the heat better than the flooded batteries. Here in Texas, without fail, I have quite a few customers that find out they have bad batteries once the temps get to the mid 90's to 100+. Battery blankets that come from the factory on most Ford vehicles don't help either. The ones that manage to survive the summer meet their end when it starts to get cold. This is why top off and test the battery as well as the charging system on every vehicle I touch.
I'll dig into the charging system on a 6.7 and see what I can come up with. I'm working on a 2018 with a dual alternator and so I have a test subject.
https://www.thebatterygenie.com/who-...sey-batteries/
"Odyssey batteries are made by EnerSys Energy Products Inc, a subsidiary of EnerSys. The batteries are manufactured with thin plate pure lead technology and use lead instead of lead alloy in other batteries. Also, the batteries have a rugged construction that is anti-vibration and prevents spillage.
EnerSys has established itself as a vital partner in heavy-duty equipment maintenance and supplies. For example, energy does not make Odyssey batteries alone but is the manufacturer of NorthStar Batteries and X2 Battery."
I got 6 years out of my original Motorcrafts. I get my truck oiled each year by Carwell Products. They use a thin oil for vehicles here in the WNY area. They spray under the hood so I've had zero issues with corrosion of the battery hold down bars and even use an oil based battery post protector.
I believe they were just getting weaak, had them tested at Advance Auto and then bought Interstate AGMs at my buddy's shop. They offer pure lead AGMs as well and due to this thread, I just learned I do not have their pure lead AGM batteries so time will tell how long these last. If I don't get six years out of them, I may have to step up to the more expensive pure lead Interstate AGM Batteries.
Cold also lets a vehicle owner know if their battery is weak because like heat, cold exposes a weak or bad battery.