The battery in my 2019 Colorado is now 6 years old, but still starts the truck just fine.
I bought a new one, but the cheapskate in me doesn’t want to put it in until I really need to. Of course, I also don’t want to be stranded somewhere.
Do you wait or do you takes your chances?
Also, in the Pit we have a regular thread for mini-rants. I don’t think this question warrants its own thread. Should we have one for mini-questions?
I wait until I get stranded in the most inconvenient place.
Historically, it’s nearly always been “replace it when it dies suddenly.”
But, my wife and I have gotten better about taking the cars in for annual maintenance checks with our local repair garage, and they check out the batteries as part of their normal checklist.
That didn’t help me this past February; we’d had my Mustang in for that service check in the spring of '24, and the battery was fine, but it proceeded to suddenly go toes-up a few months ago. It happens. shrug
I get a new battery when the old one won’t start the car. Don’t get one ahead of time. Car batteries have an expiration date and secret technology that makes them fail on the first day after that date that you need to go somewhere in a hurry or sometimes if it’s just raining or really cold out.
When the battery in my Mustang croaked in February, I had AAA come out. The technician tested the battery, saw that it was very dead, and installed a new one. He then said, “The new battery has a four-year warranty. Put a reminder in your phone to have us come out and check your battery a month before the warranty ends. If it’s getting near the end of its life, we’ll replace it for free.”
We’ll see if that helps, or if the battery croaks a day after that warranty expires. 
Right- and I have no idea what the quality (or expected lifespan) of an OEM battery is, though I don’t think I’ve ever got LESS than 5 years except in case of abuse (there have been years where my wife’s sports car didn’t get put away properly and thoroughly ate the battery over the winter)
Up until recently, I replaced it (on my ancient 2002 Subaru) the first time it failed, or I did the first two times I replaced it. After that, I replaced the battery the summer of the year before it was to expire (normally 4-5 years). Parking outside at work in Colorado Winters normally put it at the batterie’s scheduled lifetime, no more, even if it was garage parked the rest of the time.
With the new PHEV, the wife went with paid scheduled maintenance, so that’ll be on the planned dates. As for the 2007 I’m driving now? I’ll probably do the same as I did with my subie (also no real electronics to worry about) although since the wife doesn’t remember when she replaced the battery last, I do need to go check the dates on it before winter.
I have a rechargeable battery jumper box since a car or truck battery can die at any time for any reason. If it happens, I can start my truck, drive home, and they go out and get a battery from wherever I choose at my convenience. I can also use my jumper box to jump other cars with dead batteries, and I become an instant hero.
When I get the car serviced, one thing they do is to measure the charging capacity. When it’s below some threshold, it’s time for a new battery.
You can now buy car battery testers on Amazon et al fairly cheaply.
I get a new battery when my trusted local mechanic says I need a new one. Or when the car dies.
As soon as you brought the new battery home, it started aging. Its warranty certainly did. You do nothing to extend the life of the new battery by having it sit in your garage on a shelf. In fact if you don’t keep the new battery on a trickle charger, having it sit unused on your shelf is affirmatively harming the battery every day it sits ignored and unused. So you’re only exposing yourself to the sudden failure of the old one in exchange for … nothing.
The cheapskate in you fumbled the ball when it let you buy the battery you didn’t need before you needed it. With a possible small side order of absolution if you live 50 miles of dirt roads from the nearest car battery store. And own no other vehicles.
Personally, I’d rather wait until it’s -35, and the car is in my driveway.
Fair point. But my intent was to replace is prophylactically, but when I got it home lost my drive. It’s also the case that in this truck there are no fewer than five bolts / nuts to be removed and that really took the wind out of my sails. [it’s funny. I’m happy to remove the heads on my 67 Olds but replacing the battery in my 2019 Chevy is just a pain]
So now the battery is in the passengers footwell and I predict it will sit there until the current one dies.
I suppose I could just throw the jumper cables in there and then I’m covered.
I think that’s what I’ll do. Even though I know it’s dumb.
Do you carry all the tools to remove those bolts and change the battery with you in the truck? Will you remember to overnight charge the battery in the footwell every month-ish?
I have no dog in your fight, but the only thing worse than buying insurance you don’t really need is thinking you’ve bought insurance but it turns out you were mistaken and the insurance won’t really cover your problem when it matures.
All the expense, none of the coverage, and double the aggravation. What a strange game; the only way to win is not to play.
You misunderstand. I’ll put the battery on the ground and jump the truck from it.
This is fine.
ETA: I’m not actually arguing with you, @LSLGuy , I just know that when I don’t really want to do something I’m really good at not doing it you ARE right.
Six years is a long time for a battery. I’ve replaced the one in my 2016 Mazda twice, most recently about two months ago. I think 3-5 years is normal.
Check the date on the new battery you buy, it may have been sitting on the shelf for awhile. It also depends upon the type of battery that you buy. Most standard car batteries are for starting the car ONLY. I prefer a more expensive deep cylce battery, they have thicker plates and lower cold cranking ratings but will not let you down. They can be completely drained and recharged, a standrd battery if completely drained is not likely to come back, it is toast.
If you are looking for a standard starting battery I would not let one age longer than 5 years. Of course it depends upon multiple factors, like temperature, daily usage, accessories.
Car manufacturers tend to undersize the batteries in cars a bit these days, partly to save on manufacturing costs and partly to save weight. If you replace your dead battery with the largest battery that will practically fit in your vehicle, you’ll probably never have to replace the battery ever again (unless you accidentally kill it somehow).
Unfortunately, some cars don’t have enough space for the battery to allow a larger one to fit. But if you have the space, get a bigger battery.
Yep, that’s the trade-off you make with a deep cycle battery. For the same amount of lead, if you make the plates thin you end up with more surface area, which equals more cranking amps, but the battery discharges more quickly. If you make the plates thicker, you end up with less surface area, so you have fewer cranking amps, but the battery doesn’t discharge as quickly (that’s why they are called deep cycle batteries after all).
Depending on where you live and how cold it gets in the winter, you might do better with a larger standard battery than you will with a deep cycle battery. You might need those cranking amps when the temperature drops.
Either way, whether you buy a standard battery with more capacity or you buy a deep cycle battery, you’re paying more because you are buying more lead. And again, in both cases, you need to make sure that the new battery will physically fit in your vehicle.
You can still sulfate the plates on a deep cycle battery. They are a bit more rugged when it comes to being drained, but they are far from indestructible.
And to answer the OP, I have never pro-actively replaced a car battery. I only replace the battery when it can no longer do its job.
As a battery degrades over time, its internal resistance increases, and thus its CCA decreases. And it’s easily measured by applying a known load for a short period of time and measuring the voltage; you can buy handheld battery testers on Amazon for less than $40 that do exactly that. So why doesn’t a modern car have a built-in tester to do this for you? (It would periodically measure the battery’s CCAs, track these values over time, and prognosticate when your battery should be replaced.)