16 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHNew Battery
Leading reported evidence
Install exact same one (duralast agm) in my 996tt
Performed · outcome unconfirmed
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that performed work without a confirmed outcome
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed
I recently selected and installed the exact same one (Duralast AGM) in my 996TT.
Leading evidence: 'Install exact same one (duralast agm) in my 996tt' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Install exact same one (duralast agm) in my 996tt' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
In fact there is a Porsche bulletin to NOT use the CTEK or other maintainer AGM setting on their AGM batteries because the voltage is too high.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
I have no idea why the dealerships and or some battery fitment websites suggest using 600 & 700 cca batteries in our cars ?
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
The position of the battery in the 996 makes it difficult to lift the battery in and out without using your back muscles!
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.
16 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.
0 acknowledgements have no verified action link; they do not establish a repair result.
Generation: 20261027T044418Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
So the winter was not kind to the battery on my car. I have a Deka that the dealer put in the car to sell it a little over 2 years ago. Regular wet acid with 700 CCA. Upon research, the battery fits but wasn't what Deka recommends for the car as the CCA is a little on the lower side. After doing much research I decided I wanted to go with an AGM battery. I checked most of the local chains and ironically none of them sell the same name brand, but the batteries are all the same and just rebranded. Same CCA 850 and other specs. Look at the photos below of each. So I went with the Duralast as it was closest to my house and was the cheapest by $20. I'll update everyone on how it goes tomorrow.
I like Interstate. If bad and don't have receipt, they just look at the date in service. Prior owner's Interstate went bad at 27 months. Since under either their full replacement warranty (it was either 30-36 months) free replacement.
I have a 5 year old Bosch AGM battery that is still going strong, even after sitting for two months. I read that the local chains stopped carrying them because of issues with some of the batches. I'll replace it with one of the ones listed above when the time comes. It's very interesting that they're all the same but with different names.
An AGM battery is still basically a wet lead-acid battery with fine fiber glass mesh to minimize risk of spilling acid. A normal lead-acid battery maintainer/charger will work. In fact there is a Porsche bulletin to NOT use the CTEK or other maintainer AGM setting on their AGM batteries because the voltage is too high. The Optima AGM battery is designed for the slightly higher charging voltage.
AGM batteries do not need a special charger, however, it is best to get a "smart" charger/tender/maintainer. It gets the battery up to full charge and then trickle maintains the battery. I have one and it works very well on my AGM battery.
I recently selected and installed the exact same one (Duralast AGM) in my 996TT. So far so good. The main difficulty was lifting the *heavy* suckers out and back in without mashing anything. The position of the battery in the 996 makes it difficult to lift the battery in and out without using your back muscles!
I have no idea why the dealerships and or some battery fitment websites suggest using 600 & 700 cca batteries in our cars ? Mine had a Bosch Platinum 640cca H7 L4 battery original from the dealership installed 31/2 yrs ago and my car always turned over slowly. I replaced it a week ago with an Odyssey AGM 840cca and now it cranks properly. I would not install any battery less than 800cca in a 911. The AGM batteries are worth the extra few bucks as they are better batteries when compared to the average wet cell batteries.
The H7 AGM I installed was about 4lbs heavier than the wet cell H7 I took out but for the much better cranking I get now so be it .
Battery installed and it cranks over faster than in ever has. Battery was bigger than the old one and weighed more. Sucks that old battery died, but I’m happy that I now have the proper sized battery in the car.
On the flip side the old school flooded acid battery can still be a good choice . My 996 C4 runs a Walmart battery . My Boxster S runs a Tractor Supply battery . Both are 800 CCA with 3 and 2 year warranties .
If you keep them on maintainers when sitting idle you will get 5 years of service out of them . At least that has been my experience . There are only 3-4 battery manufacturers out there so shop what's available and on sale and move on 😁
I put antigravity batteries in my 991, 991 GT3 and just ordered one for my 996. Oh, also have one in my NA1 NSX. Love them! and they certainly solve the back muscle problem getting them in! Yes they are expensive (watch for the sales) but well worth it.
This is a source reference. Confirm exact model applicability in the original material.
