Do all C4's use a "Group 75" battery?

I need a new battery for my 1988 and would appreciate some recommendations. I don't want anything exotic (AGM etc.) just a good Lead-Acid battery.

Thanks,
-Wes

 

I'll never use a battery that isn't AC Delco. Just last winter I had to change my batter, my car has 102k miles on it back then probably high 90's. When I took that battery out and looked at it it was the original. Take that as you will.

 

I have yet to see a battery go 20 years. Not saying it can't happen but I haven't seen it

 

Battery's are not what they used to be . I use the Champion in all cars at the moment and they seem pretty good for the price.

 

I have been in the Solar Industry for my career and have worked with batteries for many years TOO long. The battery choices out there are getting bigger and bigger with these newer technologies becoming available.

Your Corvette was designed to use a "standard" Flooded Lead Acid battery and the charging set-points in the alternator are set for the FLA battery. There are people who try to use some new technologies and they might have problems with getting a long life out of the product.
We have a lot of years of experiences with the FLA batteries and the quality is better than it had been. I tried a Lithium Iron Phosphate battery in my 2 stroke Motorcycle and for over $125 it lasted less than 1 year even with their expensive "battery maintainer" used when the bike was quiet. It is great technology but not ready for "Prime Time" yet. The LiFe battery weighed less than a pound where the FLA version weighed over 5 pounds. That is a big difference on a light motorcycle.

AC Delco batteries are okay but I still stick with Interstate Batteries and their line of FLA batteries. The consistency of the products is what brings me back to Interstate. I have never had one fail prematurely as long as they are "maintained".
When you buy a FLA battery today there are lot of companies selling what they call a "Maintenance Free" FLA battery. These frequently have vents like the older ones did but they hide it under a sticker on top of the battery.

I will not buy any FLA battery that doesn't allow you to add distilled water as it gets used up in the electrolyte. Any FLA battery will use the water out of the electrolyte and it will need to be replaced or you can loose capacity in the battery.

The prime reason batteries are more expensive today is because the industry has decided to let you, the "consumer" of the product prepay for the recycling of the battery at the end of it's useful life. The batteries are pretty much the same as they have been for more than 100 years. Car batteries are used to start the engine and then power the ignition system. Because of this they are normally not completely charged while being used in your Corvette. The alternator will replace the current used and sometimes it might push the electrolyte to gas off a bit. I have tested batteries in several vehicles and found them to hover in the 70-80% of a full charge. Only on a long highway trip will a battery get well charged.

Every fall I remove my batteries from the Corvettes and they go on a work bench in my garage. I clean them down and then record voltage. Then I add any electrolyte to bring the level up to the normal lines. After this I charge the battery on a Four Stage battery Charger that completely charges it. From then on it is charged once a week with my big charger just to top off the battery. I will sometimes record voltages to monitor the rate of Self Discharge over a period of time. This gives me an idea of the batteries health. In the spring the connections are cleaned, the battery watered and charged and it gets re-installed.

I don't think I have ever seen a 20 year old Automotive battery that was still in service. With the technology they use to make them it is almost impossible. The compounds used to make the lead plates are detrimental to getting a long life as it slowly poisons the battery. In Europe they don't use the Antimony in "all" automotive batteries. The German Battery Company VARTA makes a Lead Selenium battery that I have seen last over 12 years in use. Lead Selenium makes for a hard plate that doesn't break down as easily. I would have looked for a build date on your old battery, it is likely the dealer changed it out for the previous owner. But with good maintenance you will see more years of useful service from your battery.
With good recycling we shouldn't ever see batteries laying in a riverbed after they were done with it. We need to be sure to recycle the old battery properly as many of the compounds are toxic and can really have a bad effect on the environment.

When buying a new battery I get it from the Interstate Dealer to get the freshest battery I can.
The very first thing you should do with your new FLA battery is to charge it "completely" before Installing it.
Many batteries that sat on a shelf partially charged will have a loss of capacity from being left partially charged for a period of time. I prefer getting a Dry Charged battery and filling it myself and forming it before putting it in the Corvette. I cringe at the thought of batteries sitting in a gas station shelf for years without being charged. If you ever work around a battery and there is a chance of getting exposed to electrolyte be sure to wear a face shield and a rubber apron along with gloves.

 

Summit has a deal going on AC delcos right now...

2 yrs ago I bought 2 basic Walmart batteries when I moved. both cars were dead.....well they held up so well, gonna replace them with the same. 150 for 2 cant beat it.

 

Costco sells Interstate batteries

 

True but I just checked. The Costco interstate battery is 650 CCA. Interstate sells 550 CCA, 650 CCA and 700 CCA with different warranties at 18, 24 Free and 5 year and 30 Free and 6 years respectively. Interstate has 3 grades. Costco has only the middle grade. So Interstate isn't simply Interstate. Depends on the grade you get

 

I've been using an Enercell from walmart for a couple years on a black & decker maintainer. Been fine for two years

 

I bought a 2000 Crown Vic in 2012, put 120k miles on it in 26 months and sold it in the summer of 2014. It had a 1999 manufacture date on the original Motorcraft battery. If I didn't drive the car for a week or so, it was hard to start but still started and then was fine after a short drive. It only died on me once and that was in Red River, NM. We went skiing for 5 days and stayed slope side at the Best Western. The car didn't move until we tried to leave. It was extremely cold that week, every night was below 0°F. We got a jump the morning we left and all was good. So apparently they can last a really long time. Still wasn't 20 years but very close to 15 years old when I sold the car.

 

I get my AC Delco 75 and 78 batteries from my local Chevrolet dealership. The 86 gets the 75 series and my Buick LeSabre and Suburban get the 78's. $88.00 for either one, out the door. I don't use any other battery. Last no-name battery I bought from Autozone died just before 3 years of age and the pro-rated amount they wanted to give me towards a new one was ridiculously low, and AZ charges exponentially more than what I pay at the dealership. I've yet to have any of my ACD's die early on me. To extend their useful life I always keep them on a trickle charger when not in use. My oldest is 7.5 years old now and still going strong.

 

Maybe whatever company makes them has improved. Bought a new 02 truck which came with a Delco...Replaced in 03 and 04. Interstate lasted 8 yrs...Walmart cheapo is 3 yrs old still going strong.
Fwiw Summit is having a sale on them, 121 a piece I believe.

 

I agree- however the price was right for me

 

Reserve capacity imo is fairly important....a 550cca doesnt spin my engine over any faster than one with 100 or more.

 

But in the cold, wouldn't it be better than a lower CCA one?

 

The majority of batteries are manufactured by Johnson Controls, East Penn and Exide and labeled for the company that markets them.

 

Yes but besides the warranty, is there a quality difference? Same factory might be used for different quality lines.

 

They do different things for the "No-Name" brand batteries. They can change the amount of expensive additives that might make the battery last longer or use less electrolyte. They can cut back on the lead used in the battery to save money. There are lots of things they can do. One of the worst Car batteries I ever bought was made by "EverReady" and did not last even a full year. I don't know who made it but I could never get the electrolyte to the correct specific gravity showing it is 100% charged.

The higher the "Cold Cranking Amps" the longer it will crank when it is cold. CCA is a rating used in the battery industry to define a battery's ability to start an engine in cold temperatures. The rating refers to the number of amps a 12-volt battery can deliver at 0°F for 30 seconds while maintaining a voltage of at least 7.2 volts. To be completely honest with you I never pay attention to the CCA as it is a bogus way to rate a battery. Maybe if I lived in Wisconsin or someplace further north.

The Cranking Amperage is a better idea of what the battery is capable of delivering. I prefer the Amp/Hour Rating system at one standard time like 8hr discharge or 12 hour discharge. Using this system they can tell you how many amps the battery is capable of making. I would then test it removing current at a fixed rate until I reach a calculated 20% remaining capacity. Then I would charge it 110% and discharge it again. After doing this a few times some batteries will make more than they are rated for. Questionable battery manufacturers overestimate the capacity on their labels. The discharge Curves speaks volumes to the experienced eye, each one is different. The discharge of a FLA battery will give you a bell shaped decline as the power is removed. If you do a discharge on a Lithium Ion battery it is totally different, the slope is Much more gradual and drop quickly getting close to the capacity. Battery Companies do the same discharges but at whatever way they want to do it. Some do 6 hour, 8 hour, 10 hour and 12 hour and choose the one that makes their product look great. I redid the tests under controlled conditions in a lab all using the same testing system. It is hard to compare batteries since the manufacturers all use different discharge rates for rating their batteries.

Since we used batteries every day in the Solar Photovoltaic Industry it benefited us to know as much as we could to get the maximum potential out of every battery we used. I worked with all the U.S. battery manufacturers and tested batteries from all over the world. It was fun to learn how they worked and to see who is telling the truth and who is not.

Battery Warranties are a Joke and only meant to get you to buy another of the same brand. I know they use the exact same batteries and sell them with different levels of warranty. The heavier cranking amperage batteries have thicker, heavier interconnects to allow the maximum power to be pulled without burning through anything.

Like I said above, I prefer to use the Interstate batteries but AC Delco is another reputable battery. I also buy the largest Cranking Amperage battery that will fit in my battery compartment. I usually buy FLA batteries with access ports to each cell allowing you to refill the distilled water used in the electrolyte.

People with batteries that are still working after 20 years of service must have got the "best" one they made that day. I have heard of people taking their original battery and dumping out the electrolyte and refilling it with fresh electrolyte hoping to get the battery to work again. VERY BAD Idea so please don't try this one. In new car applications the batteries last five and six years, why do the replacement batteries not last as long? In my opinion it is caused by the batteries being brand new and put in a Car where as the others replacement batteries go from warehouse to warehouse before the shop where you buy it.

When I buy a new Car battery I charge it up completely and then discharge it down to 80% depth of discharge and then recharge it and watch the charging curve for anything unusual. After two to three cycles the battery is ready for a long life starting your Corvette.

 

This is great information, thank you! I was reading about desulfating a battery and refilling it with distilled water to try and get it working again but you are saying this wont work? I have a battery thats been dead for a few years now and was considering draining and refilling.

 

Not based on a whole lot, but interstate batteries have been great in my c4. My previous interstate was at least 10 years old and I replaced it only because it was so old.