If I understand you correctly, you just changed your serpentine belt and (lets not worry about the car wash yet) when you start it, does it squeal? When it is idling how is it, probably okay - if you race the engine a little then you get a squeal?
If that is what is going on I believe it is your automatic belt tensioner. You do have about 133K on the vehicle. If the above is what is going on, I would change the tensioner. When the belt is off though check all the other pulley wheels for free spin, not loose, nice quiet free spin.
Then do all the above and get back with me and we can take it from there if that doesn't make a difference.
Oh, one more thing, to make sure we are on the same vehicle, I am looking at a 2000 Dodge Truck, Dakota, 4WD, V6-3.9L, VIN X (that is the 8th digit in your VIN number) If that is correct then you may have some recalls on your vehicle. The dealer may fix these for free. Please contact the dealer service department, give them the VIN number of your car and have them check on these to see if they apply to you.
Saturday, November 8th, 2008 AT 6:00 PM