AGM battery on a non AGM car?
- Thread starter slybunda
- Start date
My samurai has had the same agm for at least 12 years so I just went to check the voltage using my modified 18650 battery charger as I left my DMM at my parents house the other week. Managed to touch the wrong terminal for a split second and the magic smoke escaped. Now I’m sad.
Reply from major battery manufacturer was basically that you can run an AGM but if the car has a charging system that fluctuates based on whatever variety of factors, that may cause some concerns with an AGM battery (if it didn't come with an AGM new). They recommended I check with my car manufacturer or dealer to confirm if my vehicle charging system may need to be recalibrated, if possible, to maximize the use of an AGM battery.
So, basically how I'm seeing it in my life, seems like you can run an AGM but a solid flooded battery might be just about as good for typical driving situations.
So, basically how I'm seeing it in my life, seems like you can run an AGM but a solid flooded battery might be just about as good for typical driving situations.
If I was running an AGM in a vehicle not set up for it, I would keep an eye on the standing battery voltage with the engine off.
If I was seeing standing voltage above 12.7 I would be concerned.
Last time I checked my truck it was 12.4.
My wife's car was 12.3.
Depending on who's chart you belive, 12.7 is 100% charged.
12.5 is 80% charged.
12.0 is 50 % charged
I put a Napa AGM in my 2016 F250 last winter. There were a few recommendations about leaving the cables disconnected for 24 hours and if I recall leaving the truck off with the doors locked for the next 24 hours. Some said this was the way-others said it was a joke. I have no idea but it couldn't have hurt. I've left it multiple times with strobes running and lights on at wrecks, fire scenes, etc. since then. We also put one in my mom's F250 with no issues so far(although they're both nearly new).
If it had an AGM, it says in the owners manual of the F150, when you install a new battery you leave the truck untouched for 8 hrs to reset the state of charge.
That does not reset the BMS.
To reset the BMS.
Key on, engine off, flash high beams 5 times, step on the brakes 3 times and the battery light should flash 3 times.
I reset the BMS first, then let it sit 8 hrs.
I would think the same procedure would work on the F250.
That does not reset the BMS.
To reset the BMS.
Key on, engine off, flash high beams 5 times, step on the brakes 3 times and the battery light should flash 3 times.
I reset the BMS first, then let it sit 8 hrs.
I would think the same procedure would work on the F250.
I picked up my DMM and after resting the battery for 1.5hrs the voltage on the 12+ year old D34M is sitting at 12.85V.
Manufacturer claims full voltage should measure approximately 13.0-13.2V.
Manufacturer claims full voltage should measure approximately 13.0-13.2V.
All sales and marketing no doubt. A battery is a battery is a battery. Lead falls off the plates from vibrations and poor roads. Sediment tray fills up finally shorting out the cells. Then you get to complain on how bad the old battery was.
When did East Penn start making the F-250 trucks?
Like I had a question about vanilla ice cream. I called Sony in Japan. Their chart said.........
East Penn makes the batteries. They are not going to tell you no and lose a sale.
Yes but what they don't do is warp plates and short them out (due to the glass fibre between them) or leak.
They do sulfate and lose capacity that way
AGM has less internal resistance, = less heat creation.
And that is measurable, no discussion about it.
Go asks some offroad/racing forum if they prefer AGM or normal regarding vibrations.
I think East Penn has a chart. They have been helpful with other technical questions.
If they said sure and you ruined the battery or alternator it would not look good for East Penn.
I've used AGM in cars from the 80s and 90s and early 2000s. Never had issues. My current flooded Toyota battery (OEM) is 7.5 years old and doing fine *knock on wood* so I'm looking to replace because I'm sure it's getting close to its last crank. Another Toyota flooded is like $130 from dealer. So I'm contemplating that because I don't NEED an AGM. I just like AGMs. They give me warm fuzzies knowing I have the best battery. So now I'm scratching my head more.
Edit: and my wife's Forester has the weakest batteries known to humans. So I've wondered if an AGM would help the horrible lifespan, in my opinion.
I put an AGM in a 2015 Forester.
Golf clap.
Is it doing ok? Any issues? The websites offer them for the make and model of our cars.
No, a quality AGM will handle vibrations much better and are much more spill resistant and tolerate periods of non-use better than regular flooded cells. I started flying GA in in the mid 80's, transitioning from flooded batteries to gel than AGM and there is no comparison. AGM's have also given much better service (longer life, less electrical gremlins on the P'cars which are very sensitive to battery quality and condition) than flooded in the toy fleet.
JHZR2
Staff member
Same. Ive run them in 80s/90s care that have smaller, low output alternators. The lower impedance and lower self discharge seem to balance the undercharge and other stressing challenges m
