M932 batteries

[billystuart]

Why are there four batteries in the M923 trucks?

 

[Suprman]

So it will start in the cold

 

[Gunzy]

Probably a government contract thing. I run 2 group 31's and works fine and a lot less cost. Still have to modify the hold downs but that's not too big of a deal. I've seen where some guys run 2 group 27's. I prefer 31's.

 

[doghead]

Many big commercial trucks, run 4 batteries.

 

[emr]

probably a government contract thing I love answers like this Yea thats it ...

 

[cranetruck]

Reduces the stress on the individual batteries, they will last longer. Reserve capacity...

 

[Carlo]

I use 4 on the 923A2 cause it still uses the orginal batteries. On the M931A1 i use to Big truck batteries group 31.

 

[GHall]

Sorry to bother y'all. The batteries in my M932A1 died. I just wanted to double check how y'all charge the batteries in your trucks, do you leave them connected to each other and charge the individual batteries or disconnect them? I just wanna be sure as to not ruin these expensive batteries. I will put them on a 2 amp trickle charger. Thanks for any advice!!

 

[Suprman]

Which batteries do you have? They will usually be hawkers or the 6tmf ones. Did they die from sitting or were they fine one day and dead the next?

 

[GHall]

They say US 6TMF on the side of the batteries, brown bodies with black tops. I'm not sure how long it took for them to die, it had been 2-3 wks since I had driven it. I've had it for a long time and let it sit longer with no issues. No electronics were left on. Oh and I would like to keep from catching it on fire if I could avoid it.

 

[juanprado]

I topped mine off with acid (just a few ounces short on each one) and charged them individually as my truck was totally dead and had to be slaved twice on pick up. I used a trickle charge and they all came up nicely and have held since with no problems. More hassle but no chance one dead or shorted one will hurt the others.

 

[GHall]

Very cool, thanks gentlemen! I went ahead and disconnected them and am charging them with a 2 amp trickle. They were delivered June of 09.

 

[Suprman]

I would charge them individually on a 5-10 amp slow charge for 24 hours. See if you can get them up to 12+ volts each. If after a day you disconnect the charger for an hour or so and take a voltage reading on each battery and if it is less than 12v the battery is bad. You can disconnect the leads between the 2 banks this will isolate the 4 batteries. I had a set of these they were fine one day and done the next. I replaced the 4 with 2 diehard gold 900cca batteries but mine was in an a2 and I could crank that up with 2 car jump packs. I believe the military has been replacing the 6tmf batteries with the hawkers when replacement is due so I would think most if the 6tmf batteries out there are older to begin with.

 

[trooper632]

I have removed the four battery setup with a two battery setup, two energizer 700 cca each from Sams, works fine

 

[Scar59]

Same here, put two new 4DLT commercial tractor batteries (CCA850) from Tractor Supply in my M813 this past weekend, just touched the start swithch and fired right up. These batteries are big and long, fill the battery box with a little spacer on one side.