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Time to replace battery

When I had the oil changed on my 2007 Dodge Dakota, the service guy checked my battery and said it was “marginal”. He did not say that any of the cells were deceased. It is the original battery and I do lots of short trips requiring frequent starts.

But it has never failed and it never gets below freezing here in balmy southern California.

The service guy said that a “marginal” battery could actually harm the alternator. I have heard a much contested argument on whether charging a completely discharged battery will harm the alternator.

Is this true? Could a battery near the end of it’s happy life ham the alternator? Time for a new battery?

How was the battery tested? A load test is a good way to test a battery. If this was done, then you are probably due for a replacement. If the battery is marginal, the alternator does work harder to keep the battery charged. In the wonderful old days when cars had ammeter gauges, if the gauge inticated a high charge for quite a while after the car was started and driven a ways, it was time to check the battery and electrical system.
In your case, I would probably replace the battery.

You ought to replace your battery. I say this not because of damage to the alternator (a pervasive myth) but because the battery is at least five years old. Storage batteries don’t last forever. One rainy day your car will simply refuse to start. There is little to be gained by squeezing out another 6 months of life from your existing battery.

2007?
Yes don’t even think about it. Replace it. They don’t last forever.

If you lived in the North…then a 2007 battery should be fine. Heat is what really kills a battery. Since you said it never gets below freezing…then that tells me it’s very hot during the summer months. So 3-5 years in the south is probably about the limit of a battery life. Here in the North…I’ve had batteries last over10 years…usually at least 7 years.

“I do lots of short trips requiring frequent starts.”

I operate under similar conditions. Here’s what I suggest to get a long life out of your next battery:

Get small automatic battery charger ~5 amps and charge the battery overnight every 3 months.
It takes several hours to thoroughly charge a lead-acid battery and reduce sulfation.
Driving 10 minutes here, 30 minutes there doesn’t do the job.

I drive about 3 times a week, < 45 minutes a drive, excepting road trips.
I replace the battery every 7 years, at my convenience.
The original battery in my 2006 car is still going strong and I plan to replace it next fall.

I’d replace the battery now. This one could possibly last a bit longer, but it could die at an inconvenient time or place soon. You can’t complain about getting five or six years out of a battery.

I would go a head a replace the battery at this time. sounds like you got your money out of the orgainel battery and it will let you down at the worst time.

I’d advise replacing it now–even though my Dakota is way older than yours, I would err on the side of caution. Five years is an average life span~

Replace the battery. A service call when you are stuck in the boonies will cost you far more than a battery. You will still have to buy a battery anyway.

Old batteries can develop an internal short, which is hard on the alternator and can ruin it. But, although rare, a new battery can do the same thing if it has a manufacturing defect in it. You should get it load tested and if it is still good, top off all cells with distilled water and clean teh posts and terminals. If not, then replace.

At least this way, you are in control of the battery purchase. You can check consumers magazines for recommended brands and look for the best price, something you can’t do when you are stuck somewhere with a dead battery.

I disagree with most but agree with “Keith” 100%. Get a second opinion from someone who will at least give you the perspective that though batteries never improve in their performance, they at least can last a long time when moderate demands are placed upon them. Yes, heat is the enemy of batteries and yes, I often get ten years plus from some of my car’s batteries here in Maine. I don’t replace them every 5 years for the sake of replacing them as an expendable like motor oil and I travel with a jumper battery. Not just because I drive on an older battery but I am realistic in thinking that even my or or friends newer battery can still fail in less then 5 years of life due to other circumstances surrounding the charging system or unexpected battery failure.

IMHO, everyone should be independent in this area and not depend upon a service call for help. Carry a spare…in the same manner you carry a spare tire. BTW, you can load test it yourself. Anyone can and should be able to. They are load tested here in Maine almost every January night. The service guy wanted to sell you a battery…unnecessarily.

Every time you start the car, you connect circuitry to the plates on the inside of the battery and enable chemical processes that cause electrons to flow from one plate to the other (in each of six cells). Then, when the engine is running, the alternator essentially reverses the process. However, this chemical process includes oxidation and causes erosion of the plates over time.

Since your typical daily driving is repeated off & on cycles, your battery has experienced a great many of these chemical processes. Five years being tyoical car battery life, I’d suggest replacing it.

Your battery is nearing the end of the average lifespan of an original equipment battery. Take that for what you will. You can decide for convenience sake to replace it now as a planned maintenance item or wait until you can’t start your car one day and are late for work/school/piano lesson/etc. Now that day may be 3 years away or it may be next week. But the chances of that day happening increase every day you don’t install a new battery. I replace batteries in my cars at 6 years.

You can’t take your wife out for drinks and dinner for the price of a new quality battery, so I think it’s more a convenience issue than cost.

"You can’t take your wife out for drinks and dinner for the price of a new quality battery. . ."
That is one of Triedaq’s excuses for not taking me out for dinner–“I just bought a new battery”.

Mrs. Triedaq

Mrs T, you sound like a good lady.
Mr T, take the lady to dinner. She deserves it.

Replacing a battery where you want to- like where your tools are- when you want to- like on a day off- with the battery you want is a lot more convenient than replacing a battery wherever it does decide to die with whatever is close enough- is a good idea. I’ve done both and I’ll err on the side of 6 months early instead of a day late.

Here is a good reason to replace an older battery: In 1946, right after WW II, our family moved to a new community that had a Delco battery plant. I was 5 years old at the time. My dad was driving a 1939 Chevrolet that still had the original battery. The battery gave out and there were no replacement batteries available in our community for the most common car made. For a while, my dad was able to start the Chevrolet with the emergency crank that many prewar cars had. However, the battery finally got to the point that it didn’t have enough power for the ignition. In desperation, my dad called his brother who lived 200 miles away in another state. His brother did find a battery for the Chevrolet and had it shipped to us. Interestingly, the battery was manufactured in the Delco plant in our community.
Right after WW II, there was a pent-up demand for automobiles and for parts to keep older cars on the road. Tires and batteries were in short supply. So was housing, but that is another story.

I agree with others to get a second opinion. A good OEM battery should last about 7 years. However, if you live in Minnesota, and park outside without an engine block heater, you should replace it NOW proactively. The big test is that cold morning when you need all the juice you can get. If you live in Seattle, neither cold nor hot, your battery could last a very long time.

Lots of people telling the original poster what to do. If he asked me, I’d probably tell him to replace it now, because it’s pretty clear he’s not too informed about the entire situation, may not maintain his old one carefully or know how to squeeze one more start from a dying battery. If he has to pay for a second opinion, then just take that money and go to Costco or Wal-Mart or whatever and buy a new battery (remember to recycle the old one!).

But, for me, I have been known to wonder just how long a battery will last. Charge it every so often, clean the terminals once in a while, make sure it has electrolyte, and in a mild Northern California climate I just don’t know how long that is. My 2002 Miata has the original battery in it, still starts right up, but it’s in the perfect setting, a fairly simple car in a dry garage that stays between 50 and 75 degrees all year.