I had a mysterious rattle that was identical on two Rams. Finally had enough on the second, and found it to be the input shaft on my steering box. Just a little bit of lateral play , caused a subtle rattle at any speed, and the smallest bumps. If your ram has a steering box, grab the steering shaft just above the box and give it a wiggle. Any play at all will give you a rattle going down the road.
Btw, my solution was a large zip tie around the shaft, and through the shock tower. Just enough tension to keep the shaft from bouncing around. It feels like a new truck again.

2006 Mega 1500 4x4

 

This is also the major contributor of Death Wobble in SFA trucks. But obviously is not gonna be the issue on IFS truck owners...

 

Yes, Obviously. My first Ram was a 4x2, and never had this problem. My second was a 2000 quad cab 4x4 and developed this rattle at about 50k. I thought it was this and I thought it was that, but I never figured it out. I lived with it for another 130k. My "new" Dodge developed the same rattle at about the same mileage. That was it. No more living with it. I tracked it down, and found the easiest solution. I'm tellin' ya, 9 out of 10 subtle rattles in solid axle Rams can be attributed to the steering box input shaft.

2006 Mega 1500 4x4

 

I have an '08 with passenger side clunking over small bumps as well. Try this link:

https://dodgeforum.com/forum/3rd-gen...xed-today.html

Next trip to the dealer I'll have this printed for them




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Ditto on the Grill rattle. I finally found mine its was the metal lock bar. I imagine there are supposed to be plastic pieces on the rods to get them from making noise. Some of the grill holding hardware was loose as well. Noise is now gone.

 

Had two sources I found on mine in the past. One was a loose wind deflector on the hood (there is a TSB) and a heat shield on the exhaust.

 

Found my rattle. Piece of gravel got in behind stone guard on brakes.

 

I'm sure the OP was talking about a much deeper and heavier metallic rattle than you'd get from a piece of gravel. It's like something big and heavy is loose. Imagine, say, someone forgot to put the bushings in some component down there.




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My 06 Magnum R/T has a rattle, but stops with braking. Only over bumps. The brake pads will rattle in the caliper but are quiet with any amount of braking. I resolved mine with a new hardware kit. Essentially those little metal clips that go between the brake pads and the caliper. Remove the 2 small bolts that hold the caliper on, (dont let the caliper hang on the brake line) slide out the pads, clean everything up real nice then re-install the pads and caliper after CAREFULLY putting brake grease on the contact points. Dont get anything on the pad surfaces or disks!

 

As a technician who works on cars everyday a clunk over bumps or a metallic rattle is 85% of the time sway bar end links or bushings