I have a 2004 H2 and on the freeway around 65-75 I get a rattling noise very similar to a license plate rattling from too much base in the trunk. My music is stock and it's only on the freeway after 65ish mph

 

Check the junk in your "trunk"?

 

check to see if your exhaust heat shields are loose follow them from your exhaust manifolds down to the muffler tip and same for your skid plates make sure its not missing bolts or loose.

 

The plastic corner pieces on each side of your windshield is my guess. Common issue, they need to be sealed to the glass. Either remove them, clean the back very well and apply some VHB tape where they rest against the glass or do like most and just caulk them.

 

I've spent the last month hauling an estate clean out. This load vibrated/rattled, ONLY with the radio on.

 

I can tell you what it could easily be, since it is what happened to me.

Drove me nuts for a long time before I found the cause.
Loose car jack in its cradle.
Just loose enough to rattle, but not loose to the touch. Those have to be cranked tight into their holder.

Was that it?

 

I can tell you what it could easily be, since it is what happened to me.

Drove me nuts for a long time before I found the cause.
Loose car jack in its cradle.
Just loose enough to rattle, but not loose to the touch. Those have to be cranked tight into their holder.

Was that it?

Now I need your help.I have one of those metallic tin rattles just below the surface of the center-right front dash. Some hunk of sheet metal is loose and only rattles at certain temperatures.
If I tap on the dash pad, it rattles/vibrates.
Anyone know how to get rid of that one?

 

Okay so I finally figured out what the problem was there's a plastic piece that extends across the back of the top of the rear door and that plastic was loose and as the air pass through it it would cause it to vibrate the rattle so a little 3M adhesive problem solved

 

Wish I could help..no idea