Battery group 78

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Nov 17, 2022 | 03:29 PM

stnick

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From: Madison - Huntsville AL

Battery group 78

So my last ac/delco 42 month battery installed 6/11/13 has failed…( 9 years 5 months) of course im searching high and low for another 42 month ac/delco in huntsville al with no luck so far.
ive read on here that the group 78 will fit without any concerns/issues at all… width and height are a little less but length is 1.250 more? If the bottom sits in the tray, why not go with the higher capacity reserve and cold crank amperage ?
Thank to all that have the 78 in your baby…
Nick

Nov 17, 2022 | 04:11 PM

C5MSG2004Vert

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From: New Jersey

I used a group 34 battery with the higher capacity on my 04. Group 78 is essentially the same size with side terminals. It actually is a pretty tight fit in the tray but it mounted fine.

Nov 18, 2022 | 02:43 PM

stnick

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From: Madison - Huntsville AL

Thanks or that reply and the info… I found a acdelco 42 mth so Im hoping for 9 1/2 years out of his one😂😂

Nov 18, 2022 | 04:56 PM

JHrinsin

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From: Avon Lake OH

If I remember correctly;

1997-00 came from the factory with Group 78 wet cell battery (can be upgraded to Group 78 AGM)
2001-03 came from the factory with Group 75 AGM battery (can be upgraded to Group 78 AGM)
2004 came with a top post Group 86 AGM battery (same size as Group 75) (can be upgraded to a Group 34 AGM)

Group 78 battery is 10-1/4" L x 7-1/16" W x 7-5/16" H
Group 75/86 battery is 9-1/16" L x 7-1/16" W x 7-5/16" H
Group 34 battery is 10-1/4" L x 6-13/16" W x 7-7/8" H

Last edited by JHrinsin; Nov 20, 2022 at 08:18 AM.

Nov 18, 2022 | 05:46 PM

knewblewkorvette

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St. Jude Donor '03 thru '26

34/78 fits just fine as that's the battery I use in my C5s.
Get an AGM

Nov 19, 2022 | 03:20 AM

jdmvette

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From: Bugs Bunny should'a made a left turn here

Quote:

Originally Posted by knewblewkorvette

34/78 fits just fine as that's the battery I use in my C5s.
Get an AGM

@knewblewkorvette

is it worth it to get an AGM if it is rated lower than a standard flooded?

i am looking at costco for the replacement and the standard 78 battery for my 2000 is 800CCA/1000CA:

https://costco.interstatebatteries.c...636&Country=US

but the 2001 AGM 75 they sell rates at 650CCA/875CA:

https://costco.interstatebatteries.c...397&Country=US

Nov 19, 2022 | 09:16 AM

knewblewkorvette

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Quote:

Originally Posted by jdmvette

Definitely for piece of mind. The C5's computer is below the battery and if the battery leaks, you are looking at a major expense to repair. The AGM will not leak whereas a lead acid battery can.

Nov 19, 2022 | 09:48 AM

JHrinsin

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From: Avon Lake OH

I run an Autocraft (Johnson Controls) group 78 AGM battery 740 CCA 115 min 60 Ahr, that I bought at Advance Auto.

Some may insist on a 120 min rated AGM battery, so those would include, but not limited to;

Rural King (Exide) #RK-AGM78 group 78 AMG battery 770 CCA 120 min 60 Ahr
Deka/East Penn 9A78 Intimidator group 78 AGM battery 775 CCA 120 min 55 Ahr