2000 express 2500 with 5.0 has problems restarting if it has been ran and is up to temp and then stoped for about an hour. when the key is turned, get a series of clicks , batt has full charge.
when restarting after it is up to temp, at times get a series of clicks when the key is turned. And the volt meter on the dash will drop to about 9 volts, yet the battery has a full charge (12.7 volts) when tested will an external volt meter. Let the van sit till it is totally cooled, like over night and it will start right up.
Sounds like a bad electrical connection. I would remove the starter relay and bend the legs out to get a tighter fit. If that doesn't cure the issue, I would replace my battery cables. Especially down to the starter. Clean the starter connections as well. Clean you main grounds also. If you live on the east coast, or a state with road salt, I would say it's most likely a cable issue especially since you have a drop in voltage to your meter on the dash.
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