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Had to upgrade my battery after 2.5 years on Group 48 Replacement Battery

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YOUR RESEARCHHad to upgrade my battery after 2.5 years on Group 48 Replacement Battery

Leading reported evidence

Check alternator and it's fine

Performed · outcome unconfirmed

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Performed · outcome unconfirmed · Original poster

yes, they checked the alternator and it's fine.

Had to upgrade my battery after 2.5 years on Group 48 Replacement Battery
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Leading evidence: 'Check alternator and it's fine' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check alternator and it's fine' (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.

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Install battery tray

Performed · outcome unconfirmed

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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.

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Performed · outcome unconfirmed

What I did to get around that was to take off the battery tray, put a stainless steel bolt with a star washer through the bottom of the hole so the bolt/star washer was upside down, and then re-installed the battery tray.

Had to upgrade my battery after 2.5 years on Group 48 Replacement Battery

Install by aaa had more cca)

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 · Original poster

Interestingly, my Group 48 (installed by AAA had more CCA).

Had to upgrade my battery after 2.5 years on Group 48 Replacement Battery

Replace "porsche" labeled battery

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

Well I replaced my "Porsche" labeled battery with a group size 48 and it was an exact fit.

Had to upgrade my battery after 2.5 years on Group 48 Replacement Battery

Replace battery about a month ago

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 replaced my battery about a month ago.

Had to upgrade my battery after 2.5 years on Group 48 Replacement Battery
Frequently discussed actions (10)

These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.

Check alternator and it's fine

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
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 · Original poster

yes, they checked the alternator and it's fine.

Had to upgrade my battery after 2.5 years on Group 48 Replacement Battery

Install battery tray

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
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

What I did to get around that was to take off the battery tray, put a stainless steel bolt with a star washer through the bottom of the hole so the bolt/star washer was upside down, and then re-installed the battery tray.

Had to upgrade my battery after 2.5 years on Group 48 Replacement Battery

Install by aaa had more cca)

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
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 · Original poster

Interestingly, my Group 48 (installed by AAA had more CCA).

Had to upgrade my battery after 2.5 years on Group 48 Replacement Battery

Replace "porsche" labeled battery

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
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

Well I replaced my "Porsche" labeled battery with a group size 48 and it was an exact fit.

Had to upgrade my battery after 2.5 years on Group 48 Replacement Battery

Replace battery about a month ago

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
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 replaced my battery about a month ago.

Had to upgrade my battery after 2.5 years on Group 48 Replacement Battery

Replace fluctuation dissapeared

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
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 · Original poster

The fluctuation dissapeared when the battery was changed out

Had to upgrade my battery after 2.5 years on Group 48 Replacement Battery

Replace good interstate mtp-h7

No successful repair reported for this finding.

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Discussions that performed work without a confirmed outcome
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Performed · outcome unconfirmed

I just replaced a good Interstate MTP-H7 With a Braille endurance series 7548 AGM battery direct replacement.

Had to upgrade my battery after 2.5 years on Group 48 Replacement Battery

Use 3rd inner hole

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Discussions that contain suggestions
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Suggestion · Original poster

Group 48 battery uses the 3rd inner hole.

Had to upgrade my battery after 2.5 years on Group 48 Replacement Battery

Use 3rd inner most hole is undersized as

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Suggestion · Original poster

But 48, despite fitting and using the 3rd inner most hole is undersized as to the capacity of the battery.

Had to upgrade my battery after 2.5 years on Group 48 Replacement Battery

Use hvac system)

No successful repair reported for this finding.

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Suggestion · Original poster

On my drive of 15 miles yesterday, the voltage gauge was all over and turning on accessories made it fluctuate (especially using the HVAC system)

Had to upgrade my battery after 2.5 years on Group 48 Replacement Battery
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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.

15 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.

  • Rennlist: 1 discussions

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POST 1 / ORIGINAL POSTEROriginal post

I did a bunch of searching on here and renntech and there seems to be confusion as to which is the proper battery. Some say Group 48 is ok, some say Group 49. If you're going with something like Autozone, then for a 2003 C4s, Group 49 or the Autozone Duralast 94R-DLG is absolutely the right one. You can fit group 48 which is a smaller battery in there and it works, but after 2.5 years, I think the battery was underpowered for day to day operation and the lack of proper sizing yielded its partial demise as I started to get fluctuation in voltage between 12 and 14v (13.6v) The car still fired up, but not the first time yesterday morning after sitting for 3 days. On my drive of 15 miles yesterday, the voltage gauge was all over and turning on accessories made it fluctuate (especially using the HVAC system) So, I went with the 94R-DLG Autozone Duralast. It fits with the securing bolt/hardware using the second bolt hole. I'd call it the 'medium' battery because a longer battery would (if existed) use the outside most bolt/hardware. Group 48 battery uses the 3rd inner hole. Maybe I was just confused by the number of threads/confusion, so i'm adding my own layer of confusion for people. The 94RDLG has the terminals in the right place, with vent holes on both sides of which the positive side venthole being used w/ the stock tube. Also, as far as power, it offers 740CCA and 140CA reserve which was better than the Group 48 that Autozone had. Interestingly, my Group 48 (installed by AAA had more CCA). Guy who was knowlegable at Autozone confirmed that my Group 48 was an undersized battery.

POST 2Original post

Well I replaced my "Porsche" labeled battery with a group size 48 and it was an exact fit. So who knows. FYI I have a 2004.

POST 3Original post

There are adjustment holes to accommodate a larger battery. I used to have to fire up my car at least 10 days in between runs so my battery do not die. Then I found the drain last summer, aftermarket amp the PO had installed, and now I can hold 5 weeks before drives but it will barely crank.

POST 4 / ORIGINAL POSTEROriginal post

Quotes source post: 8326705

Yes well, the 48 does fit, as does 49. It's not about the depth (front to back) because that is the same, but it's about the width. There are 3 holes in the battery tray to accomodate 3 widths. The 49 or the 94 DLG fits with the middle hole being utilized. I'm sure there is even a larger battery which fits the entire width of the battery tray itself and that too could be correct size. But 48, despite fitting and using the 3rd inner most hole is undersized as to the capacity of the battery. I will test out my route today because I started to have PSM issues last month and there may be indication that the battery may be the culprit. This remains to be seen but battery sizing is more than physical dimensions. It's the overall ability for it to supply all the various electronic systems with the proper voltage. Interestingly enough, the OEM Porsche battery which is long gone for my car is large dimension size and identical to the 94DLG. The Autozone battery was made in Spain so I wonder if the Moll one and the Autozone Duralast 94DLG is the Moll battery in disguise. There was also another larger Autozone battery which could have fit made in the Czech Republic which makes me wonder also.

POST 5Original post

Well then I must have hit the lottery since the $45 size 47 generic Kirkland brand from Costco that we put in the CAB almost 6 years ago (March 2005) is still going strong. That's right, mine is even smaller than the 48! We only drive the car about once a week and keep it on a CTEK3300. Even has a 100 month warranty. FYI...anything from 47-49 works. ps. anybody else getting a battery ad at the top? gotta love Rennlist direct to user advertising.

POST 6Original post

Quotes source post: 8326675

You sure your alternator/voltage regulator is OK?

POST 7 / ORIGINAL POSTEROriginal post

Quotes source post: 8327043

yes, they checked the alternator and it's fine. The fluctuation dissapeared when the battery was changed out

POST 8Original post

I drive mine everyday. It might sit one or two days during the weekend if I am hauling the family around in the Expy. I replaced my battery about a month ago. My car car start turning over very slowly. New battery has been great so far. Just got back from a 300 mile day trip yesterday.

POST 9Original post

I just replaced a good Interstate MTP-H7 With a Braille endurance series 7548 AGM battery direct replacement. Braille AGM B7548 battery group 48 BCI Group: [?]Group 48 Length:10.9" (277mm) Width:6.8" (173mm) Height (without posts):7.5" (191mm) http://www.braillebattery.com/index....durance_series Interstate sizes that fit 2003 996 Group Size Interstate Type CCA1 CA/ MCA2 RC3 (Min.) Warranty (Months) Dimensions (inches) L x W x H Posts There are three holes in the battery tray they fit: H6 (48) MTP-H6 640 800 121 85 10-15/16 x 6-7/8 x 7-1/5 Top H7 (94R) MTP-H7 640 800 135 85 12-3/8 x 6-7/8 x 7-1/5 Top H8 (49) MTP-H8 720 900 176 85 13-15/16 x 6-7/8 x 7-1/5 Top

POST 10Original post

Installed the Group 49 battery (Sears Diehard Advanced Gold AGM battery, 850 CCA)... it takes up the entire tray and the retainer attaches to the last hole (the one without the threaded pre-attached nut). What I did to get around that was to take off the battery tray, put a stainless steel bolt with a star washer through the bottom of the hole so the bolt/star washer was upside down, and then re-installed the battery tray. Next, I put in the battery and battery retainer and fastened it down with a stainless steel nut with a nylon insert (or lock nut). The battery tray allows for a open ended wrench to be slid under to hold the bolt while you ratchet down the nut. You will have to remove the black panel that is next to the battery on the passenger side of the car (very simple, just one torx screw) to get your hand in there with the open ended wrench. Perfect fit, and a 1-2-3 solution for the bolt hole!

POST 11Original post

Quotes source post: 9201149

Good time to throw a cabin filter in there while the panel is out.

POST 12Original post

What battery size fits the pre-threaded hole?

POST 13Original post

Quotes source post: 9384509

There are actually 3 sizes that fit I believe, maybe just two. I think they are a BCI 48 and BCI91.

POST 14Original post

There are three holes in the battery tray they fit: H6 (48) MTP-H6 10-15/16 x 6-7/8 x 7-1/5 Top H7 (94R) MTP-H7 12-3/8 x 6-7/8 x 7-1/5 Top H8 (49) MTP-H8 13-15/16 x 6-7/8 x 7-1/5 Top The last one is not threaded. Porsche saved money on a threaded insert because you can put a nut and bolt through the clamp from the side of the tray on the largest one.

POST 15Original post

Picked up a 48 AGM from Oreilly auto parts. No vent buy. Guess that is OK. Fits perfect.

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