2008 Uplander charging problem
 

Having intermintent charging problem, I took it into the dealer and was told that is was the alternator. They replaced the alternator, I paid for the new alternator and for the labor. Left the dealership. After about thirty miles the problem returned. Took it back to the dealer, they checked it out and said it was the harness, replaced the harnes. I paid for the new harnes and labor, left the dealership and after about 40 miles the problem came back. After spending more than $1,000 getting the alternator and harness replaced, the charging system is not working.What else is there that can be bad?

the alternator sends charging voltage back to the battery through the large red cable on the alternator...this cable runs back to the stud on the starter motor and then another cable runs from the same stud back to the battery. If the nut on the starter stud is loose...the charging system light illuminate.
you can get under the vehicle and see if the cable is loose at the starter or do a voltage drop test of the insulated (power/charging circuit) circuit.

to do the voltage drop test:
start the car
-turn on every electrical load, lights, hvac, rear defrost, radio
-with a voltmeter
-put one lead on the output post on the alternator...the big red cable post
-put the other lead on the postive cable on the battery.
a good result is 0.3 volts or less...anything higher means high resistance in that cable or cable connections.

I would go back to the dealer and complain about their misdiagnosis. You went there with a problem and asked them to fix it. They guessed wrong twice and should be held accountable for their errors. I would also file a complaint with Chevrolet customer service. This is unacceptable service from that dealer.

How long have you owned this vehicle?
How many miles on it?
What do you mean by "intermitent charging problem" ?