pooszere

01 dodge 2500 Cummins diesel. Started off it turned over fast but wouldn't start. I changed a VERY CORRODED terminal end and it started. I drove it across town and shut it off then it went back to the same thing, turned over but wouldn't start again. Visually inspected cables and changed all the terminal ends but it didn't help. Now it won't even turn over. No click or anything when I turn the key. Hooked a wire to both posts of the starter it only sparked a little no click or spin. Took both batteries and the starter in for testing but they all tested good. When I put the starter back in it did turn over once slow then nothing.