Thought I'd share some sound deadening tips for the big bronco.
I have an 89XLT with the molded plastic interior panels. Between the aggressive tires, road noise, and the hollow sounds coming from the back panels, it was hard to carry on a conversation at 60 mph ('course, considering my ex-wife that wasn't such a bad idea )

Anyway, here's how I solved the problem. Went to Home Depot (any large home improvement store will do) and bought the High Density poystyrene foam that's used for exterior insulation. It comes in various thicknesses and panel sizes. I picked up a 2" thick 4'X 8' and a 1" thick piece 4' X 4' and a can of 3M #77 spray adhesive.

Take your inner panels off in the rear (more room to work with the seat out). Use a jig saw or a bread knife and start cutting pieces to fit into the body cavity on each side. Use the 1" if the 2" is too thick. With a little care you can fill up just about all the dead spaces in there. Seal the cut edges of the foam with duct tape, spray the adhesive on and put the foam panels into place. Replace the plastic panels and you're done. It will make a huge difference in the interior sound level of your rig.

You can do the front doors as well - you need to use the 1" there to make sure you clear the window when it's down.A little more work but worth it.

Hope somebody else can use this idea...

msautry
89XLT, 351, 5" lift with 32's, and some cool EB Explorer leather 6way
power seats

 

Good tip. I had an 82 Bronco that took two people to tune the radio when driving at 55. I would lean back and put my ear as close to the rear speaker as possible and my buddy would twist the tuning ****, I will try this tip in my new to me 84 Bronco.
BROKEBRONCO

 

Went to Home depot and picked up one sheet of the 3/4" stuff and it was only $5.50 for a sheet that was a 4x8 did the rear and it made a huge difference, now it sounds like a newer truck with a quiet kind of ride, hehehe to bad It runs like a old one though. Oh by the way Got my new AOD installed runs great put in a beefy mojo torque converter so it kicks pretty hard now. Thanks for the sound Tip man.

 

Good tip. I was wondering whether or not you hear any squeaking from the polystyrene. It's similar to styrafoam if I'm not mistaken, but not quite as loud. I think I'll give it a shot.

Brian
1988 Eddie Bauer

 

No problems with squeaking or anything like that. I used the foam that comes in panels for building insulation - it has a "skin" on both sides to help it maintain it's integrity. The only real problem comes from all the "sawdust" you get from cutting it. The stuff is super light and gets everywhere ;-)

I've had it in mine for a couple of years without any problems. As an added little bonus, you can consruct a 'box' of sorts around the rear speakers to help the sound quality there.