well...I think they're steel. I know the wheel part that contacts the ground is rubber, but the whole center part is steel.
And yes, a new "family portrait" is coming soon. Ive been waiting for the weather to break...and be dry. Its supposed to be 80 here on Sunday (its been a cool, windy, wet spring so far). Gonna do the first cook on the Sequoia, and if it stays dry, drag the whole collection outside for some pics.