Replacing stock 392 battery

[ParadigmDawg]

Does it clamp down same as the stock battery did ? Thought I read not compatible on this thread.

Thanks

The bigger Odessey was a perfect fit.

 

[Earl 392]

The bigger Odessey was a perfect fit.

Thank-you

 

[Johnny@JustBoltOns]

We just did the 94R on ours as well. Thank you guys for sharing this info.

Thread 'Weak Wrangler 392 Battery Life / Delayed Cranking & Starting Issues - Time for a New Odyssey 94R Battery!'

Sep 16, 2024

Good Morning Everyone,

Just replaced the battery on our own JL392 this past weekend, at least it made it to 30k but we really appreciate all the feedback we've seen on the 392 forum about battery life issues. We went with this 94R which fits perfectly!

Odyssey Battery Auto/Truck/Heavy Duty & Commercial Performance AGM Battery (94R-850) - ODP-AGM94R H7 L4



If anyone needs one, we do have them in-stock as well as other sizes (this is our sister site for drag racing stuff): https://dragracingwheels.com/odyssey-battery-1/

Recap thread on OEM battery life...

• Johnny@JustBoltOns
• Replies: 0
• Forum: Just Bolt-On Performance Parts

• 

 

[Fast-n-Furious]

Great thread! Anyone knows the weight of stock battery? I see different specs on the ODP-AGM94R H7 L4, would guess it’s heavier than stock.

 

[Mandrake]

Just wondering if you regularly use a battery tender?

I do. I have all my vehicles wired up for quick connection to a trickle charger, "a battery tender'. It's good to use. I got fifteen years on the original batteries on my 2005 Dodge ram 2500 CTD.
They are especially good in the winter when you may not have started one for a week or two.
Go out on a cold morning at 9 degrees Fahrenheit and hit it. Starts right up is a good feeling.

I call the 392 Wrangler 'Big Jeep' and my 1998 TJ, 'Little Jeep' and they have both have started on the coldest of days last winter reliably. Not a big deal for the newer 392, but that straight six in 'little Jeep', always starts!
I think I have replaced the battery twice in 'Little Jeep', and I don't think the battery needed replacing the second time. It was the starter that was the issue.
I will be surprised if I have to change the battery in 'Big Jeep' anytime soon.
Even that crazy 2021 Gladiator with the whack-a-mole 'motorcycle battery' setup, is still cranking like a champ ! ( I probably jinxed myself) LOL.

They had Type S battery chargers on sale at costco a few years back and I bought like three of them, I have a Noco, couple of Battery tenders and even a Dura-cell battery trickle charger. It's like an oddball, but works good. Keep it in the Mini.

I recommend battery /trickle chargers.

 

[5h4g]

I pulled the trigger and installed the Antigravity H7/Group-94R Lithium Battery - 80Ah. Caught it on sale for 10% off. My review:
Con: Expensive.
Pros: Engine start up (turns over fast); Battery life; Rock Slide Steps never dead/slow; Aux Switches don't shut off from low battery from normal use of accessories with engine off; Great for heavy load from aftermarket amps; Easy install; Lighter weight; Obvious quality;

Checking in on how the Anti-gravity is doing. We have two 392's and both of them have battery issues in both the summer and currently when temps have been down under 40F.
Every time I take them to the dealer the dealer says they pass the 'test'... and they tell me to wait for them to fail first. I can't have two jeeps with two batteries I'm waiting to 'fail' before they will replace them.
I've got trickle charges on both jeeps for the last 6 months. It's a catch-22... if I don't trickle charge them, the jeeps barely turn over. If I do, it keeps the batteries alive that much longer and they keep 'passing the test' at the service center.

I'm stuck in battery purgatory and open to suggestions. I've got 12.4 Liters of HEMi in the garage with under-powered alternators, and batteries that may or may not start. This isn't the Jeep Life they promised me with the extended 8-year full mopar warranty for both jeeps.

I might just bite the bullet and get some Odyssey's or anti-gravity's. But want to check in on how the AG is holding up in the cold, if you happen to see this.

 

[developerlaw]

The Antigravity is expensive but it has been a great investment for me. The Jeep can sit for a month with no charger and start no problem. Engine turns over fast. I have electric steps, rocks lights and aftermarket amplifiers for the stereo and can run for hours without the engine running. Never have to worry about the steps draining the battery. I have left the rock lights on overnight and no problem starting.

 

[5h4g]

The Antigravity is expensive but it has been a great investment for me. The Jeep can sit for a month with no charger and start no problem. Engine turns over fast. I have electric steps, rocks lights and aftermarket amplifiers for the stereo and can run for hours without the engine running. Never have to worry about the steps draining the battery. I have left the rock lights on overnight and no problem starting.

this sounds incredible. I've got electric steps, winch, way too much rigid lighting, and a tazer. Think this might be the only viable step for me and my bride to have peace of mind with our jeeps. The only thing is that it does get down below 23F here in Houston one or two days of the year. I read that you can 'warm up' the AG's by turning on your lights for a few mins which creates enough draw for the AG to heat up on its own, such that the start is no longer below 23F where it's limit is at. If that actually works, I think I can live with it.

On the other hand, ironically enough, the two days of the year when it's under 23F are also the two worst days to be stuck without a running jeep.

Out of the 40 Ah, 60 Ah, and 80 Ah options, which are appropriate for our jeep. Is the 80 needed, or just nice to have for longer runtime of accessories without the jeep running?

 

[developerlaw]

Not sure about cool weather use. I'm in North Florida and have not experienced a problem but 20 degree weather is very rare here. I got the 80 Ah but honestly have not idea what is needed. I just bought the big one so I would never have a problem . . . at the time, I had enough of my electric steps killing the battery.

 

[Bobo57]

Not sure about cool weather use. I'm in North Florida and have not experienced a problem but 20 degree weather is very rare here. I got the 80 Ah but honestly have not idea what is needed. I just bought the big one so I would never have a problem . . . at the time, I had enough of my electric steps killing the battery.

I didn't install the electric steps for just that reason, they draw a S&%T ton of power.

 

[5h4g]

Not sure about cool weather use. I'm in North Florida and have not experienced a problem but 20 degree weather is very rare here. I got the 80 Ah but honestly have not idea what is needed. I just bought the big one so I would never have a problem . . . at the time, I had enough of my electric steps killing the battery.

There's where I'm Kinda at too. Either I find a way to deal with the under-rated alternator in these things or I'm selling them both and getting a 4-cylinder Toyota.

 

[Focker]

There's where I'm Kinda at too. Either I find a way to deal with the under-rated alternator in these things or I'm selling them both and getting a 4-cylinder Toyota.

There is a way to deal with the alternator. Marco (ovrlndx) suggest this place does a beautiful job, they can use the OEM housing and make a nice setup for you:

Apex Alternators

Customized High Output Alternators

apexhighoutputalternators.com

Video is here:

 

[Bobo57]

There is a way to deal with the alternator. Marco (ovrlndx) suggest this place does a beautiful job, they can use the OEM housing and make a nice setup for you:

Apex Alternators

Customized High Output Alternators

apexhighoutputalternators.com

Video is here:

What’s the alternator issue? Haven’t heard of that yet….

 

[Jdub82]

I replaced the 60ah antigravity on my 4.7 liter land cruiser V8 with a lead acid, but I live where the temps STAY below zero for weeks on end. My only complaint was when it bricked out on those super cold stretches. Otherwise I had zero issues. A couple days in the 20s would probably be ok but long stretches around zero I’d personally advise against the antigravity. I’ve seen some other lithium with internal heaters but I can’t speak to those. If you decide to go with the AG, I’d probably get the 80ah for more cold crank on those coldest days with the 6.4liter.

 

[5h4g]

What’s the alternator issue? Haven’t heard of that yet….

I don't recall the specs mentioned but when I took mine in the service tech mentioned the alternators in these 392 application are under-rated and that this is why the batteries don't last long even being AGM's. Wish o recalled more info. I'm on our second battery on one jeep and only 12k miles on her. The wife's has 18k and without using a tender every night, it only goes a few days before it barely turns over. But when I bring it in, the dealer says it still tests out ok and they won't replace it. It's like they want me to let my wife get in a tight spot with a dead battery before they'll replace it. This is the opposite of why a family owns a jeep in the first place.
Since the dealer in 20 miles away, the battery ends up getting sufficiently charged on the drive there to pass their "test".

Purgatory. Limbo. Silly.

 

[Bobo57]

I don't recall the specs mentioned but when I took mine in the service tech mentioned the alternators in these 392 application are under-rated and that this is why the batteries don't last long even being AGM's. Wish o recalled more info. I'm on our second battery on one jeep and only 12k miles on her. The wife's has 18k and without using a tender every night, it only goes a few days before it barely turns over. But when I bring it in, the dealer says it still tests out ok and they won't replace it. It's like they want me to let my wife get in a tight spot with a dead battery before they'll replace it. This is the opposite of why a family owns a jeep in the first place.
Since the dealer in 20 miles away, the battery ends up getting sufficiently charged on the drive there to pass their "test".

Purgatory. Limbo. Silly.

With my bad battery adventure, I did some measurements to ensure everything was working right. Mine was putting out 14.7 volts when idling. Just a frame of reference.

 

[5h4g]

There is a way to deal with the alternator. Marco (ovrlndx) suggest this place does a beautiful job, they can use the OEM housing and make a nice setup for you:

Apex Alternators

Customized High Output Alternators

apexhighoutputalternators.com

Video is here:

Sent these guys a RFQ for two alternators, will report back. Thank you!

 

[EBYCREEK]

I don't recall the specs mentioned but when I took mine in the service tech mentioned the alternators in these 392 application are under-rated and that this is why the batteries don't last long even being AGM's. Wish o recalled more info. I'm on our second battery on one jeep and only 12k miles on her. The wife's has 18k and without using a tender every night, it only goes a few days before it barely turns over. But when I bring it in, the dealer says it still tests out ok and they won't replace it. It's like they want me to let my wife get in a tight spot with a dead battery before they'll replace it. This is the opposite of why a family owns a jeep in the first place.
Since the dealer in 20 miles away, the battery ends up getting sufficiently charged on the drive there to pass their "test".

Purgatory. Limbo. Silly.

Factory Alternator is 220 Amp

 

[5h4g]

I used Perplexity AI, so caveats apply, but this was the response I got regarding the stock alternator on the 392. I think (but am not sure) that the 180-amp spec refers to idle specs vs. higher rpms:

Yes, the 180-amp stock alternator is generally considered undersized for a JL392, especially when equipped with common aftermarket accessories. Here's why:

Power Requirements​

Base Vehicle Needs

• The 6.4L HEMI engine itself requires significant electrical power
• At idle, alternators produce significantly less than their rated output
• The vehicle needs approximately 100 amps just to supply existing electrical loads with all accessories on

Common Accessories Draw

• Winches can draw substantial amperage during operation
• Air compressors can pull up to 60 amps3
• Additional lighting systems
• Power steps
• Audio system upgrades

Recommended Alternator Rating​

For a typically modified JL392, alternator recommendations fall into these ranges:

• 240-270 amps for moderate builds
• Up to 300 amps for heavily modified vehicles

Many aftermarket manufacturers offer high-output alternators specifically designed for the JL platform that provide:

• 190-210 amps at idle
• Up to 270 amps at higher RPMs
• Better heat management
• Improved reliability under heavy loads

These larger alternators help prevent system voltage drops during accessory operation and reduce strain on the battery system, particularly during low-RPM situations like trail riding or when stopped with accessories running.

 

[Viking Jeeper]

I just had the dealer replace the factory warranty. It was in the final days of warranty and it failed the load test. I have used a trickle charger on it before but did not in the days leading up to the service appointment. I have a jump box if it ended up dead.