Lose all electric/power when hitting a bump

I have a 94 chevy 1 ton work van. Recently I hit a bump in the road and lost all electric and the engine died. I managed to get it started. This happened twice after that when hitting bumps. It ran fine for a few days but now if I hit a bump I lose all electric and my transmission gives out, the van will stay running now but everything else goes out! Any ideas? Sure wish I could avoid every bump in the road! LOL!

I know that this may sound silly , and you may have already checked that . but that happened to my express van , and the culprit turned out to be a loose positive lead at the battery . hope that helps .

Or the Negative Cable could be loose. Good time to clean them up and give them a good tightening. Also check the other end of the cables (e.g. connection to starter and frame or whatever). If those look OK, make sure that the connectors going to the computer are tight and clean.

Check the ground from your engine to the frame. Mine was on the right side between the engine and the trans.