I have had my van for 6 months.
Purchased from a family member. Having a few problems, i thought I would look up some info and found the many complaints about the taillights.
I found I had the same issue. With burning taillights out and turning signal (driver side)
To help people who might have this problem try this.
At night turn lights on and hit the brake pedal.
Look for you turn signal lights on you dash to glow slightly. If so the plastic around the connector melted and is allowing current to travel down brake light and turn light and vise versa. If you have some knowledge, take you brake light fixture out and look at your plug. If you see the signs of melting that is your problem!
Being a Ford man myself I will always sneer down at a GM product.
But since since I got it used well I can't complain to much about any issues I have, since I don't know how any previous drivers drove it or took care of it.