BATTERIES..

For 3rd gen Tacomas, do they require AGM batteries or can it just be a standard type? TIA

 

The good ol' regular batteries work fine. You can upgrade to AGM but will need a tune

 

This is simply untrue.
By no stretch of the imagination, do you NEED a tune to run an AGM battery.

 

The truck's charge controller is optimized for flooded (AGMs need a very slightly different voltage). Can you run AGM without tuning the charge parameters? Yes. Will it be optimal for getting the maximum life out of the battery? No.


Am I currently running AGM and havent bothered to update my tune for it? Yes.

 

The word "need" was what made the statement simply, undeniably, untrue.

 

I'll agree with you there. Optimal? no. Need? also no. It will run and charge "good enough" for many years of service. It will just never be in its optimal charge state.

 

Lead Acid is what your Taco comes with and what your ECU is tuned to charge. If you go to AGM or Lithium you will need to get into the ECU and change the tune to charge at the proper voltage for AGM or Lithium. Those take more voltage to properly charge. If I remember correctly, my stock tune charged my battery at 13.7 - 13.9 volts so if you have a scangauge or bluetooth dongle and you are reading your charging voltage if your alternator is putting out 13.5-13.9 you know it is the stock charging voltage for a lead acid battery.

I couldn't speak to how to change your tune to charge an AGM or other battery. Never walked down that road. Should be easy if you find a shop with a tuner.

• Edit: Lead Acid = "Flooded" for those of you that don't habla

 

I prefer the 12 volt kind.

 

Been running this inexpensive, probably mediocre at best AGM in my untuned Tacoma since April '18, and it hasn't "needed" a thing.
Oh, and look, no corrosion, anywhere..

 

Walmart NeverStart ( EverStart ) ...
Can't go wrong.

No need to spend an extra $100 on AGM battery - they are heavy and the alternator might need a tweak with it.

In Phoenix we replace batteries every 2 years regardless, so why pay more.
My next set ( 3 batteries for 3 vehicles will be in June of 2025 ).

 

Costco. Interstate. Non AGM

Simple and cheap.

 

So if we replace the original from factory battery that came in our 2021, that we purchased new, can I just simply replace with an Interstate (not the Costco brand) Lead Acid battery?
Sounds like the simplest thing to do and I've had Interstate Batteries last up to 7-8 years. I always go with the MP65 Heavy Duty, or equivalent, 6 year battery

 

It's that simple...

 

Costco brand? They just sell Interstate batteries. Pick whichever model you want.

 

Ive always used toyota batteries in my tacomas. They are pretty dang good

 

I tend to stick with the cheaper Costco flooded batteries as well. They work completely fine as long as you're not subjecting them to extremely high vibration (like doing the Baja 1000 for example... So-called "overland" use is quite tame by comparison).

Honestly I don't think the system voltage is optimal for ANY 12V lead acid type battery. It should be closer to 14.3V for a flooded batt, and 14.5 for AGM (and also having it be temperature-compensated, usually -0.03V/°C).

I still need to double-check on a cold morning vs. a hot afternoon, but I'm not 100% sure whether the charging system is temp-compensated... (anyone know for sure?) If it isn't, they might've simply used the lower voltage of 13.85V (what I measured on my 2018) to avoid cooking the battery in a hot climate, at the expense of battery charging efficiency in cold climates.

Lead-Acid = "Lead-Acid". AGM is every bit as much a lead-acid battery as a flooded (or FLA) battery. To say otherwise just causes confusion.

 

If you go off-road, get AGM so the sulfuric acid doesn't spill out of the vents and eat your inner fender. I run AGM in my Tacoma and basic Kirkland 24F in my street-only 4Runner.

 

I have never heard of someone using lead-acid to describe an AGM battery. AGM is the term used. You are not wrong though, flooded and AGM are both types of lead-acids. Some may differ but I would never call an AGM a lead-acid battery at any parts store or in casual conversation. I don't get that pedantic.

 

i think of those refillable 6v golf cart batteries with when someone says flooded.
i think maintenance-free (SLA/ sealed lead acid) batteries when it comes to most vehicles.
i think AGMs (absorbed glass mat) when it comes to indoor applications or marine.

 

^The OEM batteries are refillable. You can pull the caps and add water. In recent years I haven't seen any SLA batteries in common automotive sizes that aren't AGM.

Fun fact - the 12V lead acid battery next to the NiMH traction battery under the rear seat in 4th gen hybrid models isn't sealed. The owner's manual has instructions to re-attach the vent tube when replacing the battery.