rear window rattling?

My subs in my 89 chevy pickup are rattling my rear window really BAD! I s there any secrets to make it stop rattling? (its one of those split sliding ones)

First, get more damping installed onto the sheet metal of the cab.  You will have to gut the interior, especially the headliner.  You want to stop the metal from picking up and transferring the certain frequencies that are causing such a bad rattle.  When you get all the metal done, you'll no doubt find out that the window itself is okay.  The bass will sound a hundred times better, too.Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

all I can think of is to try to put some kind of rubber wedges at the top and bottom of the sliding panels but wedge them closer together if you can. Just be aware this might also create rain leaks for you tho.. Also maybe you could Dynomat the back wall of the cab just under the window might help. Lots of Dynomat.

i have a 1988 silverado extended cab with the same rear window being flexed by two 12 in. kickers, and the only solution i have found is to vent the window by opening it up just a bit. kind of hard to do if its winter you know.gcorrea