It ripped just to the outside of the inner clamp, the small one around the axle shaft. Just looks dry rotted and cracked from 11 years of Colorado summers.
I've been doing some reading on the Bilsteins, and I think you're right on getting something a little stiffer. I'm pretty sure the Tundra guys have it all figured out by part # and everything, so I'll probably go that direction. The PPO put on a Fabtech 0-2.5" adjustable "lift" - really a leveling kit I guess, but supposedly the spring rates of the coils is higher than stock, and I guess the shocks probably have more travel than stock. I think it's adusted all the way down so I'm getting no lift, just stiffer suspension in the front, but I'm not sure if OEM size Bilsteins will go right in or what, so I just figure I'll take it all back to stock form and figure it out from there.