[RICK LAKE]

rtstrack Your volt gauge could have a loose wire or weak ground. I would start with the fan belt. It sounds like it is slipping at higher rpms. The fan belt could be glazed. You didn't say how many wires go to the Alt? Sanding the pulleys with 80 girt and adding a new belt is the easiest thing to do. You need to run a seperate volt meter to the battery and then the back of the ALT and go do your short drive and monitor this meter for voltage drops. As far as grounds, I recommend a min of 2 grounds to the motor and chassic. This means no paint on the connection and use start washers. If the car cranks ok, I don't think there is a starter or battery problem, it's just the Alt or Gauge. You are checking that with the road test. May sure the belt is not slipping. If your water pump gets a coolant leak and it goes on the belt, this will cause the same problem. Check the COOLANT level when cold. Check the weep hole on the pump for ANY discolor, wetness, or stain. If any is found, you need a pump. Rick L.