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Sluggish Start, Bad Battery?

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CforHD

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I started to notice last week that the truck was sluggish to start, especially in the morning when temps were cooler.

The truck is a '22 CTD and I've read on the forums in the past that these OEM batteries only last about 3yrs. Using Project Farm's suggested battery tester, I bought the Ancel BA101 and ran the "in vehicle" test. It came back as good but noticed CCA were measured at 930. This well exceeds the 730 CCA of a single battery. I assume this is because they're in parallel and I'd need to isolate each battery by disconnecting the negative terminal.

However, if I plan to replace both batteries as suggested, can I just double the CCA (1460) in the tester to get a true result? Doing this does result in "Replace Battery" but I'm unsure of the accuracy.

Also, FWIW, I noticed a lot of corrosive build up on the passenger-side negative terminal so I suspect this is the bad battery (assuming one is bad).

Thanks.
 
I just replaced the batteries on my 22. Just under 3 year old batteries by the date stamp. Same corrosion on the passenger negative terminal. Just assume they are done and get new ones. I've noticed the newer trucks just suddenly don't start with all the computer stuff making decisions about if it should start. I'm in a warm climate and that's what happened. Which new batteries to get is a different debate but I got Walmart AGM's.
Aside from Walmart doing their own test to confirm I put a volt meter on them and was only getting like 12.24. New good batteries are around 12.6. Then when trying to start the truck they dropped down to 11.7 I think.



0513251105s.jpg
 
I got some more time tonight to test the batteries, isolated from each other. It does NOT seem that you can keep the batteries in parallel (ie. not disconnecting negative cable) and just double the CCA on the tester as I got completely different readings when testing isolated from each other.

Passenger Side

IMG_20250514_184629.jpg
I started with the passenger-side given the amount of corrosive build-up on the negative terminal. I disconnected the bracket and pried the terminal clamp off of the negative post. Leaving positive cable connected, I ran the tester and got the following:
Healthy: 77%, Charge 100%, 643 CCA, 12.82v and R=4.55
Good Battery

I deep cleaned and brushed the negative battery post clamp to remove the corrosion, placed it back on the post, tightened, and re-ran the test with the following results:
Healthy: 76%, Charge 100%, 640 CCA, 12.79v and R=4.57
Good Battery

There was a very small drop when testing from the negative battery clamp and I suspect this is due from residual dirt, moisture, etc. that may be reducing the connection quality.

Driver Side
Moving to the driver-side, I disconnected the negative cables (there's 2) and ran the test:
Healthy: 77%, Charge 100%, 642 CCA, 12.80v and R=4.56
Good Battery

This is nearly identical to the passenger side. To confirm that testing the batteries in parallel won't give an accurate result, even after cleaning the passenger-side battery, I ran the test again with all batteries connected:
Healthy: 49%, Charge 87%, 925 CCA, 12.55v and R=3.16
Bad Battery

I think this shows that you can't accurately test state of charge or CCA when left in parallel. What is interesting though, the voltage dropped to 12.55v. I would have expected this to be the same which makes me wonder if I have a different (or an additional) issue.

Conclusion / Questions

These tests were ran at 78°F while the noticeable sluggish starts the week prior the temperature was around 60°F. Would this delta in temperature make a significant difference in CCA? Is 77% battery health acceptable or is it on the cusp of being bad?

I wish I would of tested the passenger-side battery before cleaning it to get a baseline as perhaps this (temporarily) fixed the battery. Does anyone know the Mopar Part# for this passenger-side, negative post clamp?
IMG_20250515_200622.jpg
 
CforHD said:
I got some more time tonight to test the batteries, isolated from each other. It does NOT seem that you can keep the batteries in parallel (ie. not disconnecting negative cable) and just double the CCA on the tester as I got completely different readings when testing isolated from each other.

Passenger Side

View attachment 85792
I started with the passenger-side given the amount of corrosive build-up on the negative terminal. I disconnected the bracket and pried the terminal clamp off of the negative post. Leaving positive cable connected, I ran the tester and got the following:
Healthy: 77%, Charge 100%, 643 CCA, 12.82v and R=4.55
Good Battery

I deep cleaned and brushed the negative battery post clamp to remove the corrosion, placed it back on the post, tightened, and re-ran the test with the following results:
Healthy: 76%, Charge 100%, 640 CCA, 12.79v and R=4.57
Good Battery

There was a very small drop when testing from the negative battery clamp and I suspect this is due from residual dirt, moisture, etc. that may be reducing the connection quality.

Driver Side
Moving to the driver-side, I disconnected the negative cables (there's 2) and ran the test:
Healthy: 77%, Charge 100%, 642 CCA, 12.80v and R=4.56
Good Battery

This is nearly identical to the passenger side. To confirm that testing the batteries in parallel won't give an accurate result, even after cleaning the passenger-side battery, I ran the test again with all batteries connected:
Healthy: 49%, Charge 87%, 925 CCA, 12.55v and R=3.16
Bad Battery

I think this shows that you can't accurately test state of charge or CCA when left in parallel. What is interesting though, the voltage dropped to 12.55v. I would have expected this to be the same which makes me wonder if I have a different (or an additional) issue.

Conclusion / Questions

These tests were ran at 78°F while the noticeable sluggish starts the week prior the temperature was around 60°F. Would this delta in temperature make a significant difference in CCA? Is 77% battery health acceptable or is it on the cusp of being bad?

I wish I would of tested the passenger-side battery before cleaning it to get a baseline as perhaps this (temporarily) fixed the battery. Does anyone know the Mopar Part# for this passenger-side, negative post clamp?
View attachment 85793
Click to expand...
Clean it up. Should be fine. I put the felt anti corrosion washers under all four of my battery terminals.
 
One thing I found when looking into this for testing parallel batteries is to put the positive lead on the 1st battery and the negative on the 2nd. Aside from that I would disconnect them each from the truck and run the out of vehicle test. They may be fine but surprised they test at 12.8v.
 
Pearce said:
One thing I found when looking into this for testing parallel batteries is to put the positive lead on the 1st battery and the negative on the 2nd. Aside from that I would disconnect them each from the truck and run the out of vehicle test. They may be fine but surprised they test at 12.8v.
Click to expand...
Just disconnecting one negative terminal will do it. The batteries need to be disconnected from each other since they are in parallel. A good carbon pile load tester will give you an accurate result.
 
I've searched high 'n low for the negative terminal clamp connector. It's stamped with "Royal Pat. 5733152". The closest I could find was this but you have to buy 9 at a time and it's not identical. Searching Mopar parts, it appears you can only buy the entire passenger-side negative cable, including this clamp (68360692AD).
 
Are you using that one?

I'm a bit skeptical that this one would work. It's flat, missing the needed elbow to clear the top of the battery and allowing it to sit parallel. You might have enough room clock it +45° but then you'd have the rest of the negative cable assembly pulling down on this rather soft piece of metal and causing potential clearance issues with the airbox, putting it closer to the turbo, etc.

Perhaps I'm missing something?
 
CforHD said:
Are you using that one?

I'm a bit skeptical that this one would work. It's flat, missing the needed elbow to clear the top of the battery and allowing it to sit parallel. You might have enough room clock it +45° but then you'd have the rest of the negative cable assembly pulling down on this rather soft piece of metal and causing potential clearance issues with the airbox, putting it closer to the turbo, etc.

Perhaps I'm missing something?
Click to expand...
I hear ya. Not sure why cleaning up the original would not work for you. I know it had some corrosion on it but it looks fine cleaned up. There are dozens of styles available on Amazon. I guess you could go with the Mopar but seems crazy to pay for the whole assembly. I will look at some others that may work after I take a look at the one on my truck. It is cold out and I am retired without a lot to do. LOL
 
I agree; after putting in some elbow grease, I think the existing one is fine. It still has small corrosive pits and it's slightly mangled from prying it off the post but should be fine.

I feel like this should be a $10 part and if so, I'd just go ahead and replace it. At $135, its not something I'd replace at this point lol.

I appreciate it but no need to waste your time your time trying to find a direct replacement. I'll rock the existing one for another 3+ years. Thanks.
 
Update: Batteries only lasted a week. Seems 75% is when these devices report as bad so I was very close apparently.1000003708.jpg
 
CdnHO said:
I am old school and don't trust those new gizmos for battery testing. Give me an old fashioned carbon pile load tester any time. LOL. That said, does she crank over normally now?
Click to expand...
It cranks over way better now. I went with the EverStart Platinum which seems to be a forum favorite here.

One thing I noticed is the resting voltage (12.72v) seems to be slightly low for an AGM battery. I believe FLA should be in the 12.7-12.8 range while AGM should be in the 12.9-13.1 range. Do I need to program the truck to set the battery type to AGM?
 
CforHD said:
It cranks over way better now. I went with the EverStart Platinum which seems to be a forum favorite here.

One thing I noticed is the resting voltage (12.72v) seems to be slightly low for an AGM battery. I believe FLA should be in the 12.7-12.8 range while AGM should be in the 12.9-13.1 range. Do I need to program the truck to set the battery type to AGM?
Click to expand...
Mine sits at around that. Been sitting for 10 days and reading 12.67 this morning. Two new AGM batteries.
 
Last edited:
CforHD said:
It cranks over way better now. I went with the EverStart Platinum which seems to be a forum favorite here.

One thing I noticed is the resting voltage (12.72v) seems to be slightly low for an AGM battery. I believe FLA should be in the 12.7-12.8 range while AGM should be in the 12.9-13.1 range. Do I need to program the truck to set the battery type to AGM?
Click to expand...
No programming required. Just drive it.
 
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