Ok hold on a sec... there's no "DOT approval" process any part must undergo; its not the same as something like a UL label or CARB sticker. Instead the DOT sets the spec, and its up to the manufacturers to adhere to that spec.
Here's the real problem though: get in an accident running non-DOT complaint parts, and your insurance will bend over backwards to not pay. Give them ANY reason to void coverage, and they'll take it. Sometimes it doesn't even matter that the part in question had nothing to do with the accident; you violated your policy by having them on the truck so therefore they are not obligated to cover you. Period. You can sue your insurer, and sometimes you'll win and sometimes not. But either way you're gonna pay.
Depending on the non-DOT part or install too, your state's DVM has come behind those spec's and created codes (sometimes called "laws", but they're really not) for them. For example headlight or turn signal colors in California have to be a very specific thing. On the other hand, the CA DMV has no code for or against bead locks (there is a gray area here, but "beadlock"s specifically are not against DMV code; you can search for yourself here:
http://dmv.ca.gov/pubs/vctop/vc/vc.htm)
Bottom line? Those beadlocks maybe technically be legal, so you don't get a ticket. But your insurance might/probably point at them and say you violated policy, see ya later. Ya probably dont want to go there.