Battery
Le Mans Master
Joined: Feb 2003
Posts: 6,682
Likes: 144
From: Memphis Tennessee
I'm not aware of any recent technology changes that would affect a battery for the Vette.
There’s a lot of myth about batteries. The OEM batteries fitted to the C5 from 97 to 00 were of a lead acid construction. Because of a design flaw in the side posts, it was possible to over tighten the battery leads and crack the case. This allowed acid to leak into the area below the battery tray. The PCM sits below the battery tray, as does a significant part of the HVAC trunking and some wiring. Where batteries have leaked in the past, these components have been damaged. Some 11 years on, those batteries are all out of service so the risk is past.
The C5 eats batteries. It has a 20-30MA drain even when dormant so if you car sits idle for long periods, the battery will slowly discharge.
First thing is to make sure you buy a new battery that meets the GM spec. The C5 needs a Cold Cranking Ampage (CCA) of at least 500A and a reserve capacity of 80 minutes. A statement of the obvious but make sure the new battery fits the tray and you can secure it with the hold down bracket.
There are two major types of battery available; standard lead/acid construction (such as the original AC Delcos) and absorbent glass mat batteries (such as Optima Red Top). Because the acid is absorbed by the glass mat, the latter type are extremely leak resistant. A starting battery (lead/acid) is designed to deliver quick bursts of energy (such as starting engines) and has a greater plate count. The plates will also be thinner and have different material compositions. A deep cycle battery (AGM) has less instant energy but greater long-term energy delivery. Deep cycle batteries have thicker plates and can survive a number of discharge cycles but once deeply discharged are difficult to recharge.
If leak free is important to you chose an AGM battery. The disadvantage of AGM technology is that it is more expensive than lead/acid and should not be deeply discharged through lack of use. If leaks do not worry you, traditional batteries are cheaper and optimized for starting.
You then need to decide what type of use your car gets. For a daily driver where your daily commute is more than about 10 mins or doesn’t involve sitting at the lights for most of the trip, any battery will be fine. A longer journey will put back the drain from starting the car. If you have a short commute or the engine is at idle for long periods you may be draining the battery over time. If the car sits idle for days at a time, say a garage queen, the battery is slowly draining. GM gives the following advice:
“ A vehicle with a 30 mA drain and a fully-charged 70 RC battery will last 23 days. If that battery is at only 65% of full charge, it is going to last only 15 days before causing a no-start”.
If your commute is short or the car is not used regularly an AGM battery is probably not for you. If you still decide to go for one to guarantee it is leak free, invest in a battery tender and plug the battery on charge if the car sits longer than a week or so.
Armed with all that, go ahead and choose the best one for you.
There’s a lot of myth about batteries. The OEM batteries fitted to the C5 from 97 to 00 were of a lead acid construction. Because of a design flaw in the side posts, it was possible to over tighten the battery leads and crack the case. This allowed acid to leak into the area below the battery tray. The PCM sits below the battery tray, as does a significant part of the HVAC trunking and some wiring. Where batteries have leaked in the past, these components have been damaged. Some 11 years on, those batteries are all out of service so the risk is past.
The C5 eats batteries. It has a 20-30MA drain even when dormant so if you car sits idle for long periods, the battery will slowly discharge.
First thing is to make sure you buy a new battery that meets the GM spec. The C5 needs a Cold Cranking Ampage (CCA) of at least 500A and a reserve capacity of 80 minutes. A statement of the obvious but make sure the new battery fits the tray and you can secure it with the hold down bracket.
There are two major types of battery available; standard lead/acid construction (such as the original AC Delcos) and absorbent glass mat batteries (such as Optima Red Top). Because the acid is absorbed by the glass mat, the latter type are extremely leak resistant. A starting battery (lead/acid) is designed to deliver quick bursts of energy (such as starting engines) and has a greater plate count. The plates will also be thinner and have different material compositions. A deep cycle battery (AGM) has less instant energy but greater long-term energy delivery. Deep cycle batteries have thicker plates and can survive a number of discharge cycles but once deeply discharged are difficult to recharge.
If leak free is important to you chose an AGM battery. The disadvantage of AGM technology is that it is more expensive than lead/acid and should not be deeply discharged through lack of use. If leaks do not worry you, traditional batteries are cheaper and optimized for starting.
You then need to decide what type of use your car gets. For a daily driver where your daily commute is more than about 10 mins or doesn’t involve sitting at the lights for most of the trip, any battery will be fine. A longer journey will put back the drain from starting the car. If you have a short commute or the engine is at idle for long periods you may be draining the battery over time. If the car sits idle for days at a time, say a garage queen, the battery is slowly draining. GM gives the following advice:
“ A vehicle with a 30 mA drain and a fully-charged 70 RC battery will last 23 days. If that battery is at only 65% of full charge, it is going to last only 15 days before causing a no-start”.
If your commute is short or the car is not used regularly an AGM battery is probably not for you. If you still decide to go for one to guarantee it is leak free, invest in a battery tender and plug the battery on charge if the car sits longer than a week or so.
Armed with all that, go ahead and choose the best one for you.
Racer
Joined: Apr 2007
Posts: 336
Likes: 0
From: Pine Colorado
Watch this video parts 1 and 2 on C5/C6 electrical systems and ECL. Click Here
You want a battery with a least 120 RC (Reserve Capacity).
Personally, the AC-Delco Professional series with an excellent replacement warranty meets the requirements and will run you under $120. 78-6YR/7YR Different for '04 86-6YR
You want a battery with a least 120 RC (Reserve Capacity).
Personally, the AC-Delco Professional series with an excellent replacement warranty meets the requirements and will run you under $120. 78-6YR/7YR Different for '04 86-6YR
Burning Brakes
Joined: Oct 2006
Posts: 1,102
Likes: 470
From: Newark Delaware
I just replaced the battery in my '99 convertible with 33K miles. Previous owner had put a Sears Die Hard (Gold?) into it in September 2006, so that one made it 4+ years. However, there was a long stretch when he was dealing with a draw that drained the battery multiple times. Finally figured out that it was the OEM radio - replaced it and the mystery draw was gone. But the battery was never the same. Over Christmas break I was installing a new head unit so was running on battery for long stretches Even hooked up to a CTek charger the voltage kept dipping too low.
I went with a Wal-Mart battery. I've had good luck with them over the years in many cars. For $82 I get a battery with a 3-year replacement. These cars destroy batteries so if that happens within 3 years, I get a replacement. If it makes it past the 3 years, well, it's only $82.
I went with a Wal-Mart battery. I've had good luck with them over the years in many cars. For $82 I get a battery with a 3-year replacement. These cars destroy batteries so if that happens within 3 years, I get a replacement. If it makes it past the 3 years, well, it's only $82.
Pro
Joined: Oct 2006
Posts: 551
Likes: 0
From: N.J.
The battery in my 04' is the original and going to be 7 years old in a couple months,
it still works fine, it's on a tender now during winter storage and hopefully late next month after all the snow melts and the roads are clear of salty residue i will be on the road with a new batt installed.
i would like to go back to a A/C Delco but not sure how 'fresh' it would be from a dealer (you know those dates stamp codes affixed to the batt). I may just go with one from A/Z or Advance since they sell a lot of them, how many batt's are chevy dealers selling anyway ?
it still works fine, it's on a tender now during winter storage and hopefully late next month after all the snow melts and the roads are clear of salty residue i will be on the road with a new batt installed.i would like to go back to a A/C Delco but not sure how 'fresh' it would be from a dealer (you know those dates stamp codes affixed to the batt). I may just go with one from A/Z or Advance since they sell a lot of them, how many batt's are chevy dealers selling anyway ?
Thread Starter
Le Mans Master
Joined: Jan 2004
Posts: 9,488
Likes: 1,743
From: Knoxville Tn
I purchased an AC Delco Pro 78 today. My old one had CCA of less than 400 amps when tested, enough to start it under normal conditions, but the tester claimed I should change out. The battery in the car was 6 years old (AC Delco pro too). The first thing I noticed was that the HID's fired the first time without the engine running (this has never happened begore. Usuallu I had to turn 'em on and off several time, with the engine running...
Conclucion:
These cars depend on the battery for more than just starting...
Conclucion:
These cars depend on the battery for more than just starting...
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Race Director
Joined: Aug 1999
Posts: 11,113
Likes: 669
From: SE Pennsylvania
St. Jude Donor '03 thru '26
Oldtimer
Replacement battery ?
When I had my car for one year, it had the original AC Delco battery. Being worried about all the damage a leak from the AC delco battery, I put a AMG Optima Red Top in and it never had a problem. The Optima get a bad rap because 1. a lot of folks don't realize that the car has a 20-30 Ma drain on the battery, So when-ever I'm not going to use the car for 10 day or more I simply put the 'Battery-minder' Float charger on it.
The Optima battery gets a bad rap because if 2. it has to power ill -fitting radio or other electronics, the faster they kill the battery. And if you have a Optima voltage drops below 10.5 amps or lower, you can't simply put a charger on it and have it come back to life. To charge a Optima red top back, you need an extra 12 volt battery in good condition, and hook it in Parallel with the Red Top and then hook the battery charger to the extra good battery. And charge it till the Optima charge is at or above 11.2 volts, then unhook the other good battery, and simply hook the charger to the Optima and charge it to the normal 12.6 volts. At this point it is as it was before the drain took in down below 11 volts.
I have seen a lot of Corvette's that have battery problems and about 60-70% of them are because or shoddy electrical wiring or over worked battery having to power a super Amp or any other extra overloaded condition. As I said, I don't fiddle around with the electrical system, so with the use of my float charger keeps my battery always ready for the summer use.
The Optima battery gets a bad rap because if 2. it has to power ill -fitting radio or other electronics, the faster they kill the battery. And if you have a Optima voltage drops below 10.5 amps or lower, you can't simply put a charger on it and have it come back to life. To charge a Optima red top back, you need an extra 12 volt battery in good condition, and hook it in Parallel with the Red Top and then hook the battery charger to the extra good battery. And charge it till the Optima charge is at or above 11.2 volts, then unhook the other good battery, and simply hook the charger to the Optima and charge it to the normal 12.6 volts. At this point it is as it was before the drain took in down below 11 volts.
I have seen a lot of Corvette's that have battery problems and about 60-70% of them are because or shoddy electrical wiring or over worked battery having to power a super Amp or any other extra overloaded condition. As I said, I don't fiddle around with the electrical system, so with the use of my float charger keeps my battery always ready for the summer use.
Race Director
Joined: Jul 2008
Posts: 17,744
Likes: 3,671
From: The Sunshine State
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Watch this video parts 1 and 2 on C5/C6 electrical systems and ECL. Click Here
You want a battery with a least 120 RC (Reserve Capacity).
Personally, the AC-Delco Professional series with an excellent replacement warranty meets the requirements and will run you under $120. 78-6YR/7YR Different for '04 86-6YR
You want a battery with a least 120 RC (Reserve Capacity).
Personally, the AC-Delco Professional series with an excellent replacement warranty meets the requirements and will run you under $120. 78-6YR/7YR Different for '04 86-6YR
If it's not broken...
Race Director
Joined: Jul 2007
Posts: 18,681
Likes: 47
From: Reno is so close to Hell you can see Sparks , State Of Confusion
St. Jude Donor '12-'13-'14
ANYTHING but an OPTIMA!!!!.. 
Way too much money for a poorly built battery that will leave you stranded!
If you do plan to waste your money on an Optima, at least waste an extra $50 and get a Yellow Top with the 120 reserve.. The Red Top only has 100 and that just won't cut it, no matter what any die hard Optima fan will try to tell you!
Way too much money for a poorly built battery that will leave you stranded!
If you do plan to waste your money on an Optima, at least waste an extra $50 and get a Yellow Top with the 120 reserve.. The Red Top only has 100 and that just won't cut it, no matter what any die hard Optima fan will try to tell you!
I have had my Optima for 4 years now with never an issue at all.
Team Owner
Joined: May 2001
Posts: 36,836
Likes: 244
From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
Limited Warranty - 36 Months ONLY
Anyone contemplating buying an Optima starting (Red Top) battery needs to be aware of the follwing change to Optima's warranty policy, effective 2/1/09:
----------------------------------------------------------------------------------------------------------------------------------------------
OPTIMA® Batteries, Inc. Limited Consumer Warranty
February 1, 2009
OPTIMA Batteries, Inc. expects its distributors/dealers to warranty to the original user battery used within
the United States for models 34/78, 78, 75/25, 25, 34, 34R, 35, 6V; the following
Warranty:
PERSONAL/NON-COMMERCIAL USE
36-MONTH GUARANTEE
OPTIMA Batteries, Inc. guarantees to the original personal user that the above OPTIMA starting batteries
will be free from defects in material or workmanship for three years after purchase date. User must
promptly report any alleged defects to authorized distributors/dealers, provide the original sale receipt to
establish proof of purchase and warranty date, and permit examination by an authorized service
personnel.
If the authorized distributor/dealer finds the battery to be defective as a result of material or workmanship,
they will provide a replacement F.O.B. their location. All replacement batteries will be warranted for the
balance of the original warranty period.
----------------------------------------------------------------------------------------------------------------------------------------------
After this first 36 month time period, there IS no more warranty, pro-rated or otherwise. That's it.
----------------------------------------------------------------------------------------------------------------------------------------------
OPTIMA® Batteries, Inc. Limited Consumer Warranty
February 1, 2009
OPTIMA Batteries, Inc. expects its distributors/dealers to warranty to the original user battery used within
the United States for models 34/78, 78, 75/25, 25, 34, 34R, 35, 6V; the following
Warranty:
PERSONAL/NON-COMMERCIAL USE
36-MONTH GUARANTEE
OPTIMA Batteries, Inc. guarantees to the original personal user that the above OPTIMA starting batteries
will be free from defects in material or workmanship for three years after purchase date. User must
promptly report any alleged defects to authorized distributors/dealers, provide the original sale receipt to
establish proof of purchase and warranty date, and permit examination by an authorized service
personnel.
If the authorized distributor/dealer finds the battery to be defective as a result of material or workmanship,
they will provide a replacement F.O.B. their location. All replacement batteries will be warranted for the
balance of the original warranty period.
----------------------------------------------------------------------------------------------------------------------------------------------
After this first 36 month time period, there IS no more warranty, pro-rated or otherwise. That's it.
Melting Slicks
Joined: Sep 2005
Posts: 2,337
Likes: 824
From: US
Team Owner
Joined: May 2001
Posts: 36,836
Likes: 244
From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
Batteries can be purchased online as well. Personally I would avoid dealers unless you either know someone there who will give you the brother-in-law-price (wholesale) or have a business for which they will usually sell at "net" pricing.
Going online will usually save enough to make it worthwhile.
Going online will usually save enough to make it worthwhile.
Burning Brakes
Joined: May 2009
Posts: 1,197
Likes: 41
From: MEMPHIS TN
Had Red Top Optima and it would run down every week. Had to buy a charger (pita). Charger went bad so I got rid of both and got a Kirkland battery from Costco. Had it 3 years so far, no problems at all. Never had an issue.
