not really a far comparison on your setups. unless your 8D setup wwere new batteries too.
Unless I had already nearly given myself a hernia installing a pair of NEW 8D's
the week previously....
I was having issues with the side terminal versus the
top terminal battery styles. NJT used the side terminal and those are not
normally available at most truck battery places.
So while thinking things over I decided to pull the 8D's and go with the Group 31's
and not have to worry over post type crappy terminals and having to adapt
everything. A few heavy jumpers and 4 batteries and no corrosion problems.
The no-spill/fill Group 31's may have cost a bit more but so far they have held up very well even under non-ideal conditions.