M998: Loud Pop when trying to start

[Mogman]

And if you pull them make sure they actually load test them, some auto parts stores use a little hand held device that looks like a volt meter, I do not trust them.

 

[FlameRed]

Got it.

So assuming one or both batteries fail the load test at the auto parts store, what is everyone using as a replacement? I am sure the auto parts guys will try to tell me their off-the-shelf car ones will work just fine.

The military batteries are hard to come by and close to $600 each from what I am seeing. Are they worth it, as that is what I have now. Here is one I see people are using on other threads:

https://www.osibatteries.com/replacement-exide-6tagm-battery-12v-sealed-rechargeable-vrla

 

[Mogman]

For that kind of money I am a big fan of Odyssey batteries (PC2250) many get "regular" batteries like Red Top and get adapters to properly mount them.
And again I would only use sealed AGM batteries.
Are these the ones that came from DRMO with the truck?

 

[Coug]

Got it.

So assuming one or both batteries fail the load test at the auto parts store, what is everyone using as a replacement? I am sure the auto parts guys will try to tell me their off-the-shelf car ones will work just fine.

The military batteries are hard to come by and close to $600 each from what I am seeing. Are they worth it, as that is what I have now. Here is one I see people are using on other threads:

https://www.osibatteries.com/replacement-exide-6tagm-battery-12v-sealed-rechargeable-vrla

The 6TL battery is only rated around 700-750 CCA.
The H1 with identical drivetrain to the HMMWV had 800 CCA batteries.

The group 24 battery will work with the original military hold down bracket if you get the flat top version. You can find them in 550 CCA versions up to over 800 CCA versions.
Unless you are wanting to run a lot of electronics with the truck turned off, pretty much any pair of batteries of decent size with at least 700 CCA rating will work. I've even heard of people that have run lawnmower batteries (300 CCA rating) and the trucks started no issues for a while, but I wouldn't trust anything that small in anything other than 70+ degree weather.

The military uses 6T batteries in the HMMWV because they run the 6T battery in all of the other trucks, and the military finds it much easier to stock a single battery type for all their fleet, even if it's oversized for the application.



My take on batteries is this:

If your truck never leaves cell phone coverage, and is always where someone can easily come give you a jump start, then run whatever batteries you want. Lots of people seem to be satisfied with el cheapo walmart group 24 batteries. At minimum though a maintenance free version saves the headache of having to check fluid levels every month.

the 6TL batteries you find in most auto parts stores (usually special order though) only come with a 6 month specialty battery warranty. Some people are happy with them, but other people have had them fail in under 1 year of time and been very disappointed in them.

If you like to go out on the trails or go overlanding, or leave cell phone coverage, then buying a good quality battery is important.
Spending the extra money to get AGM type batteries is well worth it. They are maintenance free, and much more resistant to vibrations and abuse than flooded lead acid batteries.
The two main brands in the U.S. are NorthStar and Odyssey.
Odyssey or Hawker are pretty much the only ones to buy if you insist on getting the 6TAGM battery (both brands are owned by the same parent company, and are just 2 different labels for the same battery).
For group 24 AGM batteries then Batteries Plus sells them with a 5 year full replacement warranty (EDIT: Currently it's a 4 year warranty not 5) for about half the cost you'd pay for the 6TAGM, and specs are about 2/3 of the 6TAGM across the board. Also nice to be able to buy and pick up locally if you have a batteriesplus nearby, as it can be hard to get online sellers to honor warranties, or you have to pay extra to ship them the bad battery to be tested, and pay to ship the new one as well, as warranties don't normally cover shipping charges.

Optima used to be a good brand, but they moved their production to Mexico many years ago and the quality suffered dramatically as a result. Some people still swear by them because of their past experiences, but the newer versions just aren't as good.


Here is a link to a page about HMMWV battery choices and things to think about. I don't agree with everything discussed about them, but it does have a lot of good info.

Humvee Upgrade: Best HMMWV Batteries | Gear Report

Everything you ever wanted to know about the batteries in a military HMMWV. What batteries to buy, how to keep them charged, how to secure them in the vehicle, etc.

gear-report.com

 

[Maxjeep1]

I went with the Hawkers. I believe they were 932.00 shipped. I had a lead time because they are made to order. I didn’t want batteries to cause other issues and I still don’t know how to jump start it properly. Batteries were my only splurge item and they weren’t much more than the other high end batteries. I have the Dakar or whatever gp puts in them in one of my trucks and I will not change them until they fail.

 

[FlameRed]

Thanks for all the tips. I plan on taking both batteries out to get them both tested. They don't have the date checked off on the stickers so I don't know for sure. They are the old Excide ones. I don't know if the prior owner changed them, or if those are the ones that came with it originally.

I agree that Optima has gone down hill. Long ago, they were my go2 battery. Back in the day, I had Optima's that lasted over 10 years and probably would have kept going except I sold the cars. Not anymore from what everyone tells me.

I would not have thought to look at Batteries Plus. They do have a Odyssey 6TL that is pretty pricey.

If one battery fails and other passes, I am guessing it is a good idea to consider buying two so the two batteries remain in balance? Especially if one is under sized. And I suspect that the other one would be ready to go soon anyway and avoid wasting another day waiting for a tow! Besides, not the greatest to have one sealed and one lead-acid I am thinking.

 

[Mogman]

One reason I run high end batteries is we (the wife and I) run down the 4WD section of the S Padre beach several times a year, 62 miles one way with no cell phone service and at times you can drive 25 miles or more without even seeing another soul, then you turn around and drive 62 miles back because you run into a "cut" through the island.
I want batteries to be the last thing to worry about.

 

[Mogman]

Thanks for all the tips. I plan on taking both batteries out to get them both tested. They don't have the date checked off on the stickers so I don't know for sure. They are the old Excide ones. I don't know if the prior owner changed them, or if those are the ones that came with it originally.

I agree that Optima has gone down hill. Long ago, they were my go2 battery. Back in the day, I had Optima's that lasted over 10 years and probably would have kept going except I sold the cars. Not anymore from what everyone tells me.

I would not have thought to look at Batteries Plus. They do have a Odyssey 6TL that is pretty pricey.

If one battery fails and other passes, I am guessing it is a good idea to consider buying two so the two batteries remain in balance? Especially if one that remains is under sized. And I suspect that the other one would be ready to go soon anyway and avoid wasting another day waiting for a tow! Besides, not the greatest to have one sealed and one lead-acid I am thinking.

Yes you should ALWAYS replace both of the batteries at the same time, especially if you are using high end batteries (read if you are getting used "tested" batteries or cheap batteries than what the heck you are going to be changing batteries allot anyway)

 

[MarkM]

Actually TOBIAS has a good point, given you waited so long to disclose a cap had been blown off a battery and your limited troubleshooting skills it would be best at this point to pull the batteries and have someone test them before proceeding.

I concur. Start with the basics. I suspect you have a real problem with at least one battery. Those caps don't just "pop" off.

Mark

 

[Mogman]

The batteries must be in the same condition and age so they are "balanced" this is so they last as long as possible, you should even try to get batteries with the same lot number and or build date, even if they have one on the rack that is a couple months newer try to get a "matched" pair.

 

[Coug]

closely matched batteries is more important with the old 60 amp system because it has no mechanism built in to keep the batteries balanced.

It's also a good idea to either use an external 12V charger on each battery once a month to equalize the charge level in them, or to swap their positions once a month. The forward battery tends to charge a little more than the rear battery. It's not much; just the way a series battery system works, and eventually it can lead to premature failures if something isn't done to correct it.


The dual voltage systems are a little less picky about the batteries being perfectly matched, as the rear battery has both a draw on it as well as it's own charging circuit, but it's still a good idea to keep them closely matched if that's possible.

 

[FlameRed]

Thanks everyone for all the guidance.

Last night, I took the one battery that blew the cap to the local Pep Boys that still has one of those "old school" Frankenstein battery testers. that sits on the floor and looks like it 100 years old. As I have seen it in action before, it made some nice buzzing noices when he started it up and then a huge bang! But I knew enough to stand on the other end of the store! No one was hurt. Needless to say it did not pass. Of course they wanted to sell me something, but I thanked them and went on my way. Even with my hand cart I left with a fresh hernia!

I appreciate the tip on Batteries Plus. They had the best deal on a Odyssey 1225CCA 6TL AMG. I found threads where others on this forum use them. Even with sales tax, they are a lot less than perhaps shady, online vendors as I got a 10% discount and there is no shipping charges. They would not let me order two in one order but no problem ordering two in two seperate orders. They told me that I needed to order them online to get the 10% discount. They had 500 in their warehouse in Wisconsin so it might be a couple weeks before I see them. Said they come with a 4 year warranty and I can bring them back to the local store for an exchange.

 

[Mogman]

closely matched batteries is more important with the old 60 amp system because it has no mechanism built in to keep the batteries balanced.

It's also a good idea to either use an external 12V charger on each battery once a month to equalize the charge level in them, or to swap their positions once a month. The forward battery tends to charge a little more than the rear battery. It's not much; just the way a series battery system works, and eventually it can lead to premature failures if something isn't done to correct it.


The dual voltage systems are a little less picky about the batteries being perfectly matched, as the rear battery has both a draw on it as well as it's own charging circuit, but it's still a good idea to keep them closely matched if that's possible.

That is only true if you are drawing current from the "low" side battery, all the 14V tap on the regulator can do is add current to the low side battery to compensate for the extra current draw it cannot subtract current from the low side battery so it cannot truly balance the system unless as I said you are drawing current from the low side battery.
A three speed system converted to 200A like this one will not be drawing any current from the low side battery.

 

[Mogman]

I think you will like the Odyssey batteries, from what I have read they have an average 10 year life expectancy

 

[FlameRed]

I wanted to thank the forum members that guided me on this issue. You all saved me throwing parts at it, saving me lots of $ and aggravation. Much appreciated!

It started right up with the two new batteries.

In case this information is useful to someone in the future, while the Odyssey is the same size as the military batteries I had, the top shape of the Odyssey is a little different and I could not make the original battery hold downs fit at all. So I fab my own battery hold downs from aluminum I got from Lowes. I think it was better to keep the original holder rather than beating into something unrecognizable. Nothing fancy since I cannot weld but it holds them in nice and secure. The original battery hold down j bolts looked really good so I reused them.

I got new military type terminals, new military red rubber terminal covers but reused all the cables as they looked fine. I will coat the terminals with that greasy gue slime. What a messy job!

But all good and back in business

 

[Mogman]

I wanted to thank the forum members that guided me on this issue. You all saved me throwing parts at it, saving me lots of $ and aggravation. Much appreciated!

It started right up with the two new batteries.

In case this information is useful to someone in the future, while the Odyssey is the same size as the military batteries I had, the top shape of the Odyssey is a little different and I could not make the original battery hold downs fit at all. So I fab my own battery hold downs from aluminum I got from Lowes. I think it was better to keep the original holder rather than beating into something unrecognizable. Nothing fancy since I cannot weld but it holds them in nice and secure. The original battery hold down j bolts looked really good so I reused them.

I got new military type terminals, new military red rubber terminal covers but reused all the cables as they looked fine. I will coat the terminals with that greasy gue slime. What a messy job!

But all good and back in business

You can "trim" the original hold down bracket to fit.

 

[Mogman]

Glad to see you get her going again!!! and that the wife is no longer sitting on a hydrogen bomb!