Group size 75 vs 75/86 batteries

[dlundblad]

My truck takes the group size 75 battery. Typical GM side threaded terminal post thing. Did a bit of googling and found the group size 75/86. Same side posts, but normal top posts as well. Assuming it fits, anyone see any issues with these?

My main hesitation is their local availability A quick Google shows Oreilly and AAP carry them, but only in their economy line with a 1 year warranty. Batteries Plus has them in AGM, but are more than double the price.

 

[mrsilv04]

My '04 Silverado takes a group 78. I use a 34/78, to get the top posts as well.

I use the top posts for easier jump starting of other vehicles, and have pulled that battery out and dropped it in another vehicle with top posts in a pinch.

I'm lucky in that I can get a 34/78 from Rural King for $59, with a 1 year free/5 year pro-rated warranty.

I've also used the Rural King 34/78 batteries in my '00 Sierra, and in a '03 Ford V10 Motorhome. I like the versatility.

 

[c502cid]

If you have the room you can use the 34/78 dual terminal too. Higher CCA but larger in dimensions.

Edit: mrsilv04 beat me to it.

 

[dlundblad]

I might give the RK battery a look. I’ll be going out that way tomorrow.

 

[pcoxe]

I used a side/top post battery in a car once, and for some reason the negative side post went dead. I was able to move the cable to the top post and got several more years out of the battery. I've heard from others that side posts tend to do that sometimes.

 

[zzyzzx]

My truck takes the group size 75 battery. Typical GM side threaded terminal post thing. Did a bit of googling and found the group size 75/86. Same side posts, but normal top posts as well. Assuming it fits, anyone see any issues with these?

I've been using a group 75/86 battery in my Alero for years. At some point I'm probably just going to replace the side post cables with slightly linger top post cables and just start using Group 86 after that. I also hate side posts.

 

[dlundblad]

Been using the same RK battery since Fall 2021. Not bad for an ~$80 battery.

 

[ChrisMU]

I put a Group 75 dual terminal battery in my ‘76 Coupe DeVille. It is an Econocraft from Autozone and priced at $89 + exchange. Despite the massive engine bay, the area for the battery is small, so a group 78 might not fit. I wanted the dual terminals for easy charging. Charging at the side terminals on that car risks hitting the metal inner fender unless you raise or wedge the battery upward. I’m in Texas, with no plans to visit family up north, so Rural King wasn’t an option.

 

[Randy_R]

Group 78 fractionally larger than 75. 78 should fit. I use 34/78 in my Tempest. Connect MSD box to side posts.

 

[zzyzzx]

I'm still trying to determine if the group 75 battery hold down wedge will still work if I put in a slightly narrower (by about 7mm) group 86 battery.