Should a Battery be Replaced Before it's Dead?

If anyone really knows, should a battery be replaced before it no longer holds a charge? My mechanic recommended changing the 5-yo battery on our 2008 Scion before the winter, even though it still fired up the car without a problem. He felt that a worn battery would affect spark plug ignition. (This comes on the heels of replacing ignition coils and plugs.) It wasn't an expensive job, and he is honest. Thoughts?

 

It strains the alternator, thats it.

As long as you have over 13v the ignition runs fine.

The first thing to shut down is usually the electric power steering, they require more current and will bind and cause a very heavy feel.

Next is accessories like lighting and hvac.

Low on the list from my experience is ignition. It runs of 5v and 12v very low current.

I recommend batteries every 5 years as well, but to promote alternator life, and reduce risk of a no-start.

 

The batteries only job really is to start the truck. After that the alternator powers everything. So it would have no effect on ign spark. But, you should replace a old battery before winter at least to avoid being stranded with a dead battery.

 

Thing is that the cold is much more likely to kill an older battery, as in going to work one morning and not being able to start your car. It’s not a bad idea if you’re worried about being stranded. That said I don’t think I’ve ever replaced a battery that still started my vehicle or took a charge.

 

Ditto. You got your money's worth.

 

New Battery's are way cheaper then a tow and getting stuck alone in the middle of winter not able to start it. Battery's and Tires which is the only connection to the road I value my life on at 60-70 MPH in traffic. I change both before they go bad!!

True story on our dirt loop road in the middle of nowhere and winter I decided to take the long way to town that night. Came across a Caddy that was dead in the road in the snow when it was super cold. I stopped and asked what was wrong and the guy said my battery is dead and it won't start?? He was not even dressed for winter just regular shirt and pants with tennis shoes on! Not even a jacket! After chewing him out I jumped his car got him unstuck and followed him out. He would have died that night if I had not came by. His battery would not start his car again leaving the lights on a little bit even tho he had gas still! Think about it is it worth the cost of one? Depends on where you live and drive.

 

No, not at all. But you need to ensure that it dies at the worst possible time and the worst possible place.

 

I would say yes, change the battery before it dies. I’m not saying change it every x or y years but look for the signs. Signs include slow crank, battery acid leaking from the caps or nodes, corrosion on the top, and battery acid going down to the ground. Battery acid is corrosive and I’ve lifted up cars and seen it go straight down from the tray and eat up all the paint on the way down.

 

One of the best tools I've bought is a Clore BA9 battery CCA tester. I test our batteries at every oil change.
It seems very accurate and new batteries have tested within ~10% of their rated CCA (usually on the high side).
I believe it shows to replace the battery when it gets below 80% of the rated CCA.

 

What he said ^^^
Auto parts store give free load tests to determine CCAs = life left in battery.

 

Should you fill up with gas before you run out, or after?

 

A battery has 2 jobs. One is to start the engine. The second is to absorb voltage spikes from the charging system. It does not create or improve ignition spark or quality. If the battery does not start the vehicle or hold a charge, then it should be replaced. If it is leaking, damages, swelling or off gassing it should be replaced. Other then that, run it until it gives up.

 

I’m in the same boat, my battery is 5 years old. Still holds 12.4v overnight and looks to be in good shape.

 

Victoria is easy mode for a car. Never gets super cold or super hot!

 

You said it brother. It’s the fountain of youth for vehicles.

 

Batteries should be treated like any other maintenance item. They should be replaced at certain intervals and not wait for them to fail. If you wait for one to fail it will always do so at an in opportune time or at a bad location. I replace my batteries every 5 years no matter what. I use Costco or Walmart batteries, 27 series and they cost about $100. That cost works out to be $20 a year, or about $1.66 a month, damn cheap. You don’t really save any money by getting another 6 months or year out of your battery. And replacing it at certain intervals you don’t have to worry about it failing.
I run Costco or Walmart batteries in my cars, trucks and boats. Over 20 years I had only one that failed under 5 years and it was covered under warranty. I wouldn’t even think about keeping a battery until it failed. Replace them at what ever interval you think fits your situation, some areas are much harder on batteries than others. Think of it the same as spark plugs, or oil, replace them at specific intervals. Easy peasy, no problems, no worries, cost effective.

 

For my "normal use" vehicles, I keep batteries until I have to recharge them, then I'm off to the store for a replacement.

The biggest surprise I ever had was the original battery in my Tacoma died when I was on a road trip. I had driven it seven hours the previous day, so it should have been fully charged. No slow starting the next day, it just "clicked." Thankfully I was at my sister's house and she had jumper cables. I drove straight to Advance Auto to have it checked and replaced. That battery had never given me any slow starting...just a quick near-death. It was almost 7 years old when it died, so I guess I got everything out of it.