Tailgate striker
 

I searched and couldn't find what I was looking for. Google was no help, either.

Has anyone ever adjusted the tailgate strikers? Here's a pic of what I'm talking about, the rubber bumper part.

http://img710.imageshack.us/img710/408/0219111940.jpg

Here it is with the rubber part removed, it's a torx headed bolt:

http://img101.imageshack.us/img101/6290/0219111939.jpg

I thought maybe I'd try screwing them out a little further and see if it made my tailgate more solid. I couldn't budge either side, though. On the one on the right, the plastic knob-looking part at the rear moved with the bolt. I stopped before I tore something up.

Anyone have any ideas if they are supposed to be adjustable?

I seem to remember taking mine off once before. I was removing the inside panels and the plastic knob was in the way. Now I can't remember if I actually removed them or if I only thought about how much easier it would have been if I had. :(

I just went and checked and the plastic knob rotates with the screw like you said yours did. It was very difficult to turn in either direction. I didn't want to force it or use pliers on the plastic part. In my experience the plastic GM used is pretty brittle. You could add a couple of layers of duct tape to the front (or on the tailgate itself) to increase the thickness a little bit.

BTW; those plastic knobs are there to hold the oem cargo net in place.

Mystery solved! I wondered what the knobs were for. My cargo net was long gone before I got the Blazer. To be honest, the tailgate isn't floppy or anything. It just moves a little bit when you close the back glass. I was cleaning it out today and noticed the rubber bumpers and got curious.