[77newell]

Since truckers are using more battery power for running stuff while parked with the engine off there are new batteries being produced that blur the line between what we refer to as "house" batteries and regular starting batteries. Size 31 batteries of this sort are mass produced and since 3 of them match a pair of 8D's they may be a cheaper alterative if you can fit them in the space available. I think size 31 is the scommon truck size I checked out but now I can't locate the reference document. Still, the technology applies and you can check it out at your battery supplier.