Why is my new AC Delco replacement battery not fitting correctly?

[Brian E.]

My car is a 67 427 / 390 horse without air conditioning My car is a 67 Corvette 427 / 390 horse without air conditioning. The battery (and heat shield) sits on a welded steel battery tray that mounts on the passenger side frame rail. Near the bottom of the battery tray, the tray grips the battery on the front surface of the battery with an integrated hold down and on the rear surface of the battery with a separate hold down clamp.
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The battery that was in my car when I purchased (5 years ago) my car was a 24PG 88865263 (pictured below), which fit and functioned perfectly and has the following attributes:
• Correct terminal orientation,
• 700 CCA,
• indentations in both surfaces near the bottom of the battery for the battery tray hold downs,
• the 42 month replacement warranty,
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According to my AC Delco shop as well a separate GM dealership, X years ago the AC Delco 24PG 88865263 battery was replaced with 24GHR 88866250 which has all the same attributes except for one… Where the case for the older 24PG 88865263 has concave-shaped indentations for the battery tray hold downs, the case for the newer 24GHR 88866250 has large flanges (see pix below).
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These new flanges are bigger than what the original OEM battery tray hold downs can handle. After trying with all my might, I can get only the slightest edge of the flange under the front battery tray hold down and I’m worried that’s not enough. In case anyone is wondering, yes, the heat shield is installed correctly and is not interfering with the fitment.
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Is this a problem?
Will this battery be secure?
Has anyone else experienced this fitment problem?
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Thanks in advance for your help.

[Edward J.]

Brian,I have a 9 year old professional Delco Battery I put in my 63 that I had to modify, It has a handle to carry it easily, I used a cutting wheel to cut the mounts off the battery so the hold down would work. I think the batteries today are meant to work with alot of GM cars. From looking at you pick the are 3 raised ribs, maybe if you grind them down the battery will slip into the tray some to give you enough room? I also think if you go with lesser Delco battery 3 year warranty the configuration is different, my friend just brought a new Delco battery that did not have the handle like mine is.

[Brian E.]

I just got off the phone with AC Delco, and I'm not surprised that my call was a waste of time because the type of person I need to talk with is an AC Delco engineer who could tell me if those flanges are solid (or not). I don't mind cutting into a $150 battery and potentially ruining the battery. My bigger concern is what's inside the flanges... is there a cavity with battery acid inside the flange (not likely) or are the flanges 100% solid without battery acid inside them. Again, I'm not as concerned with ruining a battery as I am potentially weakening the ability for the battery case to absolutely (under all conditions and circumstances) contain the battery acid without pouring out onto my car's frame.

[Mark E.]

How frustrating! Sometimes it's the simple stuff that trips you up.

You may need to be flexible with brand and reuse the ACDelco stickers from the old battery for looks. For example, I believe Duralast has indentations. See photos here:

Duralast Group Size 24 Battery

https://www.autozone.com/batteries-s...-dl/959510_0_0

And yes, it's important the battery is well secured. You don't want it breaking loose in a collision.

[Joe L.]

I just got off the phone with AC Delco, and I'm not surprised that my call was a waste of time because the type of person I need to talk with is an AC Delco engineer who could tell me if those flanges are solid (or not). I don't mind cutting into a $150 battery and potentially ruining the battery. My bigger concern is what's inside the flanges... is there a cavity with battery acid inside the flange (not likely) or are the flanges 100% solid without battery acid inside them. Again, I'm not as concerned with ruining a battery as I am potentially weakening the ability for the battery case to absolutely (under all conditions and circumstances) contain the battery acid without pouring out onto my car's frame.

Brian-----


First of all, I think that the degree of engagement that you can obtain with the existing battery hold downs and the new Delco battery flanges is sufficient to retain the battery.

However, I am very confident that you could modify the battery flanges to increase the retention without causing any problems, at all, with the battery. There's no way that these flanges are "hollow" and "wet". I'm very confident that they are solid plastic. Plus, the amount of material that you would need to remove to substantially increase the hold-down retention is quite minimal. Very careful use of a dremel-like tool should work wonders. That's exactly what I would do if I ever had this problem, assuming that I was not satisfied with the unmodified degree of retention.

[Tim S.]

Last I knew, the Delco batteries are just a Chinese manufactured unit though Johnson Controls. Not exactly a high quality piece. Nonetheless, it's what you need to minimize judging deductions. Not surprised with your experience Brian, and it summarizes the ongoing struggle with restoring and maintaining these cars.

[Joe L.]

Last I knew, the Delco batteries are just a Chinese manufactured unit though Johnson Controls. Not exactly a high quality piece. Nonetheless, it's what you need to minimize judging deductions. Not surprised with your experience Brian, and it summarizes the ongoing struggle with restoring and maintaining these cars.

Tim-----

As far as I know, Johnson Controls and Exide are the two major manufacturers of automotive batteries. All or most all batteries, regardless of brand, are now manufactured by one or the other. Of course, that does not mean that all of the batteries manufactured by either company are all the same----they manufacture batteries to different specifications. So, while Delco batteries may be manufactured by Johnson Controls, that does not mean that they are the same as those manufactured for, say, Walmart's "value battery line".

As far as I know, GM/Delco has not manufactured a battery in many years---all of their battery plants were long ago sold to other companies or just closed as they got out of the battery manufacturing business and divested of most of their other parts manufacturing businesses. As I vaguely recall, some time ago they had to "take back" one of the plants and went back into the battery manufacturing business but I do not know if they still have that plant in operation.

Once-upon-a-time, when GM was in the battery manufacturing business they actually had battery plants located all over the country. Since batteries are heavy and thus expensive to ship, I suppose the rationale was to have the plants relatively close to the end users and/or GM vehicle assembly plants.

[Brian E.]

With a fair amount of embarrassment I'll share what I learned... The reason the flange of the battery was not fitting well under the front / fixed hold down is because my battery's heat shield was lifting it off the battery tray. The part of the heat shield that sits under the battery was bent preventing the battery from sitting perfectly flush on the battery tray. Take a look at the pictures below and you'll see what I mean. Today, the new battery is sitting securely in/on the battery tray.
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[Joseph S.]

With a fair amount of embarrassment I'll share what I learned... The reason the flange of the battery was not fitting well under the front / fixed hold down is because my battery's heat shield was lifting it off the battery tray. The part of the heat shield that sits under the battery was bent preventing the battery from sitting perfectly flush on the battery tray. Take a look at the pictures below and you'll see what I mean. Today, the new battery is sitting securely in/on the battery tray.
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Great catch!

[Bob H.]

looking at a 24s for my 63. Anyone used this one?

[Gary B.]

looking at a 24s for my 63. Anyone used this one?

Bob,

I think you’re more likely to get an answer if you start a new thread that mentions 24s battery and ‘63 in the title.

Gary