Dyna Beads, two words.
You can find them here:
http://www.innovativebalancing.com/index.php They can be found locally at RV places, but there are several choices, so shop wisely.
Yes, BBs, soft pellets, golf balls, and all sorts of crazy stuff has been used, and some of it actually works. There are many threads on this subject, and reviews are mixed. Loved 'em/Hated 'em. Place me in the former, though I understand some of their limitations.
First, the powders (Equal) may not be the best for 4wheeling, because they are useless when wet, and may never be powder again. A tire can burp while submerged, and let a little water in. No more powder.
I prefer the (larger diameter) offroad Dyna Bead, which cannot be added through the valve, but neither will it come out the valve. (They make filters for that .) The website makes recommendations for ounces needed per tire size, and I would assume that formula would work for anything short of pancake mix.
The arguments for beads are strong, the best argument against may be that "they don't work." Cannot argue with that, but for me, they do work. I did have a 5000 mile mostly road trip to sort it all out, finding a slight shake at higher pressures (60-65lbs), on a 235 85 16 mounted on stock 4Runner rims on a 98 Tacoma. Lowered the pressure below 55 pounds, and no trouble at all. I like that I can lower the pressure to whatever I want, offroad wherever, whenever, gather rocks, mud, junk on tire, air up, and hit the interstate with no balancing issues. And never lose a weight, and never have to balance at all.
As I recall, I purchased the 30oz bag, divided it equally in 5 parts, and asked the tire installer to carefully pour the contents of each baggy in the tire before seating it on the rim. You can hear the beads by simply rolling the tire/wheel on pavement, or sometimes even driving slowly on a smooth, quiet street. It does take a little bit of rotation of the wheels before the magic balancing act occurs. But, it does.
I know, no pics.
Musta been purty boring.
Dale