By way of follow-up, Batteries + Bulbs did their test. Battery was dropping to 8V, so they swapped the battery out.
Free AGM > Buying new Lead-Acid
Thank you @JohnJB!
Question to Battery Gurus... (13 Viewers)
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Free AGM > Buying new Lead-Acid
Thank you @JohnJB!
I just bought the X2 SLI 31AGM DPM. ON the top it says it requires a float charge of between 13.5 & 13.8. Anyone know what our alternators kick out?
Also, I am only going to have a single battery for the impending future. I will run a few LED lights and a NL 60 fridge. I have a HAM radio that will mainly be sued while under way. Other than that no real draining items. Any thoughts on IF this will work well. My travels are typically overnight and then back on the road again. Fridge will only be on for trips, otherwise it will remain in the shop on a shelf....
With a solid charge this new battery (never been used) is showing 13.01 volts.
They are temperature compensating alternators. On my truck I measured cold idle voltage at 13.85V and warm idle voltage at 13.4V but YMMV.
I think it is the bulk and absorption voltage you want, not necessarily the float. But I could be wrong.
I think it is the bulk and absorption voltage you want, not necessarily the float. But I could be wrong.
i add the diode to the alt-s circuit when I bought a optima yellowtop. I recently decided to get a 12v usb cig adapter with voltage readout. Over 2 800+ mile days the voltage rarely fell below 14v. Was over 14.2 most of the time. The voltage may be 'high' on the adapter, but even so it is more than I thought.
Overall though, I wish I had a basic SLA and the yellowtop is already compromised with what I think is a failing cell.
Overall though, I wish I had a basic SLA and the yellowtop is already compromised with what I think is a failing cell.
That seems high. It could just be a cheap and poorly calibrated meter though
for bulk charge >14V is ok but you need to float at a lower voltage or you’ll slowly cook the battery. Unlike a wet cell, you can’t add more water to a sealed AGM. (While they are sealed they can still vent if overcharged).
Yeah, the obd tool runs a few 10ths lower For voltage, I need to stick a multimeter 9n it and find the offset, I think both those sources are prone to error.
A few years ago I saw this thread and installed the Interstate 31p-agm7 with the Slee battery tray…
Well… it’s dead now. Only 10% health.
It there a better battery that fits in the Slee tray? Why did it die so soon? Should I change out the alternator? I use the CTEK charger monthly as suggested here.
Well… it’s dead now. Only 10% health.
It there a better battery that fits in the Slee tray? Why did it die so soon? Should I change out the alternator? I use the CTEK charger monthly as suggested here.
RET2
SILVER Star
There is so much info that needs to be known before a concrete answer could be given. House battery? connections clean and tight, which CTEK charger and which battery isolator are you using etc.
Thank you for your help! See attached pictures (I didn’t want to say the wrong thing). I really don’t want to buy a new $300-400 battery every 3 years so any advice is greatly appreciated.
Just buy a cheap $100 wet cell. Our batteries are mounted upwards so the only advantages to AGM for us is that you get ~2x the number of deep cycles and you don't have to occasionally add water. The downsides are you need the diode hack to get the charging profile correct, if you overcharge and they vent you can't just add water to get them back to a usable state, and given they cost 2x as much so it's roughly the same cost to just replace your wet cell every 3 or 4 years than to try and maintain an AGM to get 6-8 years out of it.
My $0.02, which isn't worth stopping to pick up most of the time.
My $0.02, which isn't worth stopping to pick up most of the time.
Judging from that 12/18 sticker on your battery, you're within the 36 month free replacement period for that particular battery.
Rushing to the interstate dealer as we speak. THANK YOU
But for future reference, how do you extend the life of this battery so it doesn’t die in 3 years like mine? Any ideas on what I could have done wrong?
But for future reference, how do you extend the life of this battery so it doesn’t die in 3 years like mine? Any ideas on what I could have done wrong?
I'm far from an AGM evangelist as it relates to 200 series usage. I concur with the previous post by @linuxgod and I don't really warrant the need for my personal use.
That said, I've inherited two trucks with AGMs under the hood, my last 200 had an X2Power AGM and my current truck has a Northstar AGM. I've not experienced a premature battery failure but I cannot truly speak to long term battery health. My old truck's X2Power is now maybe 4 years old and it's still kickin' for the new owner (he thought the battery went out but actually it was the more dreaded starter failure). I'm not sure how old my current Northstar is without looking at it. In both cases, the trucks are running a diode mod and receiving, at minimum, bi-monthly charges from a Noco charger. The only issue I've had is with the terminal extension oxidation issues that requires some maintenance.
And with that, I likely just jinxed my current battery. Should it fail outside the 48 month free replacement warranty period, I will remove the diode mod and switch back to FLA.
Where can I get information on the diode mod? I did not know to do this. It wasn’t included in anything I read.
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Ideal Alternator Output?
What should we expect to see for alternator voltage output on a healthy alternator? If it matters, I have a 2013. I've had a couple of variations of the HKB diode (fixed .6v increase and variable increase up to 1.0v), but all of a sudden I seem to be seeing lower charging voltage than I was...
forum.ih8mud.com
That might be one of the more succinct threads regarding alternator output/AGM charging/diode mod as it relates to 08-15 200s (16+ is another can of worms). It gets mentioned in passing in a lot of other threads. I believe it's more frequently, or was a more frequently, discussed topic in the Tacoma/T4R world.
So what would be the wet cell equivalent of the 31P-AGM7? The Cruiser is 2014 and I think I am getting ready to get my third Interstate battery. Clearly need to either switch to a wet cell or do the diode mod.
So following up to my post from January 2022. Went with the Interstate AGM again. And I need to go back to Interstate again to replace the battery again. This time I ran it with the diode mod and no luck. Got almost exactly 3 years of life out of it to the day. lol
To confirm, you got 3 years with your Interstate AGM WITH the diode mod?
If so, that seems like a short amount of time. Though my OEM panasonic looks to have 52% starting CCA per my recent battery test ("good - recharge" reading fwiw). It's almost 3 years old and trickle charged when parked for a while. I noticed some sulfation evidence on the tie down strap - scant amount of white crusty stuff). Looks like it's not going to make my 5 yr goal on this beloved battery. I think my neck of the woods and heat is just destined to destroy these batteries.
If so, that seems like a short amount of time. Though my OEM panasonic looks to have 52% starting CCA per my recent battery test ("good - recharge" reading fwiw). It's almost 3 years old and trickle charged when parked for a while. I noticed some sulfation evidence on the tie down strap - scant amount of white crusty stuff). Looks like it's not going to make my 5 yr goal on this beloved battery. I think my neck of the woods and heat is just destined to destroy these batteries.
