I just wanted to know which size Optima Red's to get. I am aware that the battery temp sensor needs to touch firmly against the bottom of them. I want the largest I can install, even If I have to do a little modifying to the trays.

Which size batteries?

How much modifying to make them fit?

Thanks Guys! :0

Tom

 

My dad bought a couple of Optima #sc34u from me they are really close in size to a group 24, just a little shorter in height. They drop right in and require no mods for fitment. These things work great! I've only had to warranty 1 becuase it froze, ps don't overcharge them either, i.e. they don't like being overcooked on a battery charger.


P/N# SC34U

Cold Cranking Amps @ 0*F 800
Cranking Amps @ 32*F 1000
Reserve Capacity 110 min
Length 10"
Width 6 7/8"
Height 7 13/16"
Type Post/Terminal Dual SAE & GM (top & side post)
BCI Group 34/78

 

Optima just released a Group 31 that might need some looking at.

900 CCA @ 0 deg. F
1125 CCA @ 32 deg. F
155 reserve
12 13/16 length
6 1/2 wide
9 3/8 tall 59.8 lbs

Not sure if they will fit our trucks. There was some discussion about Group 31 batteries being close to fitting.

All this was in the Feb 05 FourWheeler, page 87

 

Even a coventional 31 is a darn good battery, couldn't imagine an Optima version

 

Youre talkiing about the yellowtop???

I priced them out.....Over $310 each (Canadian).......ouch. Picked up Deka/Penn Power Commercial Group 31's for $100 each......looks like Ill be fitting them in -30 temps....

 

I would love that group 31. But, I wonder if it would fit?

 

Group 31's???...Some say yes, some say no. Really depends on each battery since they vary in size a bit but as far as I can tell, and from the dimensions its going to be pretty close. Maybe some minor trimming of the battery tray and changing the hold down may be required.

Will be nice having 1000 cca, 1190 ca, and 195 minutes reserve.....

 

I bet a group 31 would fit. If you go to the Interstate Battery site they show factory replacement being a group 27 which is a little smaller I think only a tad narrower

http://www.ibsa.com/estore/search.as...KQQWE1MR9&js=1

 

an Interstate group 31 spec is:

Weight: 61 pounds
Length: 13 inches
Width: 6.75 inches
Height: 9.38 inches
Cranking Amps: 1190
Cold Cranking Amps: 950
Voltage: 12
Termination: T

an Interstate group 27 spec is:

Weight: 50 pounds
Length: 12.06 inches
Width: 6.81 inches
Height: 8.88 inches
Cranking Amps: 940
Cold Cranking Amps: 750
Voltage: 12
Termination: A

Pretty darn close betcha could fool that battery tray

 

I didnt know the optimas had those kind of CCAs.
But if they do looks like I will be picking up that Group 31 when I need batteries next. Ive heard way too many good things and also too much good experience with optima to go with something else.
Just a quick question, how many amps is our Alt on our trucks?

Thanks

-Jared

 

Well,
The only rub is that the numbers for that group 31 were specifically from a Yellow top battery. That's VERY expensive for two! I was hoping to get a Red top. BUT, their reserve capacity are around 105 min. That's not so great. The price difference would be somewhere about $50-60 per battery. I'm not so sure I want to spend $300-325.

So, I will be looking a little closer for a big Red top pair......

Tom

 

Don't get swayed by the CCA on batteries. You have 2 so if the connections are in top shape you get twice the load.
RC is the big one to watch. If you have to cycle the grid heaters 2 or 3 times before starting the RC or reserve capacity means just as much as CCA.
I have an Espar. It killed a set of group 34 Exides. Group 34 is what you would get with Optima Red Top.
Optima is a very nice battery ( have one in the mommy van), but they rate no better than a comparable battery for CA, CCA, and RC.

I went with a Sears Diehard group 27 battery. They work great for my demand.
The only comparable Optima is a group 31 yellow top. Again, the Optima specs rate no better than any group 31.

I had my drive side battery out of the truck last night testing the grid heater relays. I forgot to measure the tray size.

My 2 reale

 

Here's something to consider about Optima red tops. I've had one in my Jeep CJ-7 for 10+ years and it appears it might have finally given up the ghost just a week or so back. Before the Optima I had 4 top of the line Sears Die-Hard batteries and none of them lasted more than 2-3 years with the last one leaving me stranded in the boonies on the last day of elk hunting - swore I'd never have another Die-Hard again after that. I put the Optima in when I got home and have never regretted it. It's started the Jeep in all kinds of temps, especially low temps (like -10 to -35 F) and done numerous winchings and never seemed to strain from anything I threw at it. I don't know about anyone else but I've never heard of any other battery lasting like this one did.

Steve