Brick nose group 31 question

Rot Box

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Sorry in advance for beating a dead horse.. :idiot: I'd like to install group 31's in my 91 F350. From what I have gathered they will/should fit without much headache but I'm not sure how to secure them to the tray.

My batteries are secured in place with that plastic black clamp that bolts to the tray and clamps onto the side of the battery. Do group 31's have the same notch on the bottom for the clamp to grab onto or do I need to make brackets/straps that go over the top of the battery? If I need the straps is there a quick way to get ahold of some maybe from a different year/make/model vehicle? I'm going on a trip next weekend and I don't have much time to fiddle around with it so I may have to pass and get the 31's the next time around--hoping not.

Thoughts on this one? http://www.interstatebatteries.com/...-batteries-31p-mhd-31p-mhd?dsNav=N~2147384903 Friend of mine is an Interstate dealer. Thanks again,


Andrew
 

SLC97SR5

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I don't have any experience with the G31's but that looks like a solid battery. I use the MTP-65's and they have done well.

I wouldn't miss an opportunity to upgrade. What about ghetto rigging them into place with a couple ratchet straps then after the trip you could source/build a proper mount?

It looks like they are only a couple bucks more than the OEM size for a couple hundred more amps.

Do it!
 

dunk

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I'm about to bite the bullet on 31s for my 86... Just trying to find local supplier for 2/0 cable before I buy the batteries. In any event Pep Boys has 25% off order online pickup in store. $139 battery becomes $104 at 950 cca. Tractor Supply is $100 for a 925 cca gr31. NAPA is at $108 for a 925 cca gr31. That's the three lowest price I've found. Pep Boys is heaviest at 6 lbs heavier than the others, I think I'm gonna do theirs as I've always shopped batteries by weight and just bought whatever was most ccas that fit and heaviest. Hoping new group 31 batteries and new cables will keep it spinning fast as it nears single digits.
 

73idi88f350

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This is what I did in my 88 when i installed groups 31s you will need to ether add something to the bottom of the battery trays or cut the one lip off sorry no pics of that and then I just bent up some steel and got some battery j hooks
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IDIoit

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i put a set of group 31's into my 90 F350.
ran into the same problem.
ratchet straps worked great.
the only reason the hold downs are on these battries is so they dont jump around. only reason.
if ratchet straps are ghetto, what do you call battries that are not strapped down?
 

sjwelds

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^^^yeah this lol. in my 92 I just cut a chunk of 1/4" aluminum plate to lay in the factory tray so the batteries wouldn't ride on the lip. so far all I've got is a bungee cord holding them in place. the other day I noticed that the plate had slid far enough out from under the batt that it had hit the fan shroud lol. need to do something professional one of these days
 

Rot Box

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Thanks guys I appreciate the help. I'm found some CAT batteries locally that are a group 65 (like stock) with 880 CCA which would give me about 60 more CCA's than a typical replacement. I think 31's would still be the best option but I'm kinda thinking I might give these batteries a try for now.. Can't make up my mind. I wonder how good CAT batteries are. They're made for construction equipment so I'm betting they have to hold up to more abuse... I am/was an Interstate fan but the last two have swelled and started leaking within the first year. First world problems right? LOL
 

73idi88f350

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FYI batteries break down from vibrations best to strap them down right, now the ratchet strap idea will work
 

dunk

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Got my batteries, cable, terminals, etc. and ready to do the swap and make the cables. Just need to figure out hold downs. Is there a good off the shelf hold down that'll work for these? I've used those cheesy parts store jobbies before and they break after a few months. Both the thick wire with a thin L channel on each side and the thick plastic on each side with the stretchy center. Would be nice to have a substantial hold down for these, but I have a feeling I'll have to make them myself.

I like the ones 73idi88f350 made. I may end up doing similar. I would also add rubber to the bottom of them where they touch the batteries. I keep old tire tubes for stuff like this, glue to bottom and good to go. I also use those soft/grippy acid mat things under my batteries both to minimize vibration and try to save the battery trays.
 

cpdenton

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Just a bit of info. Advance auto has the group 65s that are 850 cca's. I have them and they have been great. Order them online one at a time and use the coupon code wd46. Should be 50 dollars off each one, as long as you order them one at a time, or go in store one at a time....

This is what I did.
 

82F100SWB

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Cat batteries are great, especially their group 31's.
As for holddowns, if you can find them stock 86 and older ones work great with no mods.
 

73idi88f350

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Got my batteries, cable, terminals, etc. and ready to do the swap and make the cables. Just need to figure out hold downs. Is there a good off the shelf hold down that'll work for these? I've used those cheesy parts store jobbies before and they break after a few months. Both the thick wire with a thin L channel on each side and the thick plastic on each side with the stretchy center. Would be nice to have a substantial hold down for these, but I have a feeling I'll have to make them myself.

I like the ones 73idi88f350 made. I may end up doing similar. I would also add rubber to the bottom of them where they touch the batteries. I keep old tire tubes for stuff like this, glue to bottom and good to go. I also use those soft/grippy acid mat things under my batteries both to minimize vibration and try to save the battery trays.

Yes adding rubber would be a nice touch and since you've said that I may do like u said with an old inner tube. These were really easy to make, I have a pair of air metal scissors so I cut out a few strips bent hem over on a vice drilled the holes. Then threw some paint on them.

My batteries are so firm I can rock my truck from them lol.

I paid 114each I believe for the oreillys super start group 31s I have there brand batteries in my other cars and have been happy with them so far.
 
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dunk

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Mine were $104/ea at NAPA. Normally $120-$140-ish, forget what he said. Asked if they price matched because tractor supply had 925cca for $100, said that's as low as he could go and good enough for me to save an extra stop and these are 25cca more than TS. Paid a little premium for the 2/0 but whatever, only place I could find it local and my cables are really crap, like surprised it starts as well as it does.

Pulled my drivers side battery tray and the whole bracket BS for the rad and washer tank, blasted all the rust off and waiting for paint to dry to reinstall. The group 31 fits the tray just fine with room to spare all around, no need to grind the lip on an '86. My battery tray is rough though. I got a repop tray and bracket for passenger side I put in but have not seen any for drivers side. Know if anyone makes these? I could probably patch mine up or make one if I had to but off the shelf is easier. Mine should be good for a while longer now but I'd prefer new and solid.

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73idi88f350

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i think 87 was the year they changed the trays... 86 and older no mod to the tray 86 and newer mod tray..
 
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