Chevrolet Repair: same gauge problem, different vehicles, chevy venture, circut board

Question
I have a 2004 Chevy Venture and a 2003 Ram 1500 Quad cab Hemi.    I have the same problem occurring in both rigs.  The gauge clusters work erratically.  On the Dodge, the Tach and speedo don't report correctly or at all, about 90% of the time.  On the Chevy, the Fuel and speedo don't report correctly about 50% of the time.  Both are Automatics and both have ABS.  One other thing I notice with the Venture is that every time I shut it off and get out, I get a pretty good shock when I go to close the door!  Could this be related?  Maybe a bad ground or something?  Where should I start to look for the solution?

Answer
Hi Scott... it is always good to check the grounds...but i would be more inclined to look for a problem in the wiring to the dash cluster. the dashs have a printed circut board in them that sometimes crack and make them act up, or maybe bad connection at the dash...try unpluging them and cleaning contacts. the shock has me puzzeled, could be power going to ground. check the battery and alt power wires for chafing to ground. that could also cause your dash problem.hope this helps