I concur with ciras3 as I had an identical problem with my 98 the terminals corroded and one was stripped (where the wire attaches to the side post.)
I bought a new battery(biggest size and CCA money could buy) as the threads were stripped.Replaced both battery ends while I was in there sealed them with battery terminal protector (paint type stuff).
After I had tested the alternator and found that it was cooked due to bad connections .I was running on direct battery voltage,so drove to the parts store and got the new alt and installed it then and there as tools were in the back.Now everything was all good and no more
It made a difference in the way the electrical stuff ran.