Battery Life Expectancy ???

Doug E · 07-30-2002, 06:07 PM

Reading another thread got me wondering, what is the average battery life in a 911?

Right now there is a "DURALAST" battery in my '81 SC which was there when I bought the car last summer. I have no paperwork indicating how old the battery is, so with-out a battery tester is there anyway to guesstimate how old it is?

As a follow-up, what type of battery are others using?

TIA

Jim Richards · 07-30-2002, 07:12 PM

Doug E, my experience with car batteries in general is they're reliable for maybe 3 years, then after that, it's a crap shoot. Most of that experience was in the South, where the heat can sap the life out of anything. Maybe it's not as bad here in NoVA.

GeorgeK · 07-30-2002, 09:21 PM

For a given Ampers and Ah value, buy the heaviest you can find (in std, not the dry cell type). More weight means more electrode plates, which ARE the source of durability.
The Bosch in my 930 is 8 years old, going OK, the Crappy unit in the Cup car did one(!)year.
A factor to consider is suspension stiffness. A hard sprung car will shake a battery to death, by bridging the electrodes.
GeorgeK

FlaCarrera · 07-31-2002, 09:44 AM

I just replaced a monster that a PO had installed with a physically smaller but well endowed Interstate. I was lucky that the Interstate delivery guy pulled up at the shop same time I did. This gave us a chance to compare vars. sizes & pick max. cranking amps for that size before installing and buying. He actually unloaded several off his truick to do this...nice guy!

Have you checked the sticker label on the battery itself? There may be a Yr Mo hole punched out indicating purchase date.
Cheers
Ted in So. Fla
86 Carrera Blk/Blk

Rot 911 · 07-31-2002, 09:51 AM

For life expectancy I have had better luck with Interstate batteries than any other battery I have ever used. But to be fair, I had a Walmart battery in my MGB for 5 years with no problems.

Ted Stringer · 07-31-2002, 09:56 AM

I never seem to get more than 2 yrs out of a battery. It dosn't matter if its a large diesel or some small car w/easy to turn moter. Then again I live in FL

pwd72s · 10:14 AM

The Optima in my old Dodge pickemup is over 10 years now....Porsche batteries, Sonnenschien gel cells, are about 3 years now...both still going strong. Optima in Cindy's '99 Ranger is going into year three.

Doug Zielke · 07-31-2002, 10:17 AM

Good point about vibration taking it's toll on batteries. That's why m/c batteries often give up the ghost long before their automotive counterparts. The better quality batteries have reinforced plates to resist vibration.

Sulfation (caused by lack of use) is another killer of lead-acid
storage batteries. If you use your car infrequently, keep a self-regulating trickle charger on the battery. I like the "Battery Tender" brand. I use these chargers on all the toys, and find they extend battery life considerably.

barlowdo · 07-31-2002, 10:18 AM

I have found that the constant drain that newer vehicles put on batteries for remote start, security systems, computer and so on seem to kill batteries quite quickly. My girlfriends 96 Jeep goes thru Die Hard batteries about every two years. Usually a cell goes bad.

I have been told that in the future they may even go to much higher voltage batteries.

I actually thought cold weather was the worst thing for batteries. But at least you usually get a warning. I had the 7 year old battery go in my '86 Jeep just recently with no warning after a very hot heat spell in the sunny south.

The same battery has been in my 911 for at least 4 years and is still doing well - knock on wood.

A battery sitting around with no trickle charge can die fast also.

I thought I would get smart and use a trolling motor deep cycle battery in my car. The cranking amps were not as high but I thought I would get more longevity out of it. This did not appear to be the case as it died as fast as any of my car batteries.

To get to your question I would guess it is an older battery if it is one of those factory filled low maintenance ones. It appears that manufactures have gone back to batteries that you can add water to thru caps on the top.

Does it have the punch out holes in it for warranty purposes ?

-Don

Jim T · 07-31-2002, 11:26 AM

I've had unbelievable good luck with Interstate.

On average, they have lasted close to 10 years for me, under varying conditions, in daily drivers and in cars that see use every week or two (although in the limited use cars, I try to stick a trickle charger on them every now and then).

I've tried others, including Pep Boys (never lasted more than a couple years, although they would replace under warranty) and Die Hard (not bad, but not as good as Interstate).

Doug E · 07-31-2002, 01:36 PM

Good idea on the possibility of a sticker. I'll check when I get home later.

Doug E · 07-31-2002, 05:44 PM

Just checked and there is no sticker.

Interestingly enough it says it has a 7 year warranty but since I don't know the age I guess it doesn't matter.

I'll pick-up up a battery tester sometime but until then I am just going to keep on driving and not worry about it...

barlowdo · 08-06-2002, 06:59 AM

You may be able to take the battery in and at least have a load test done on it . This should at least tell you if it is going bad or not.

By the way the battery that lasted the longest for me in my Jeep was a Chapion 825/630

-Don