My wife hasn't seen it yet

[Geoff Winnington-Ball (RIP)]

Originally Posted by Phill

Strangely when my son turns the steering wheel, standing in front, the machine seems to move.

That's a good thing, Phil. What happens with standard carrier steering is that for the first x-degrees the steering mechanism slides a crosstube connecting the forward bogies back & forth, warping the track to either side for a slight change in direction. Beyond that x-degree point, the steering mechanism applies the brake on whatever side you're turning toward, thus slowing that track and allowing the other side to slew the carrier around. Historically it's a simple but effective mechanism but with the caveat that the brakes tend to wear out unevenly and prematurely; with the T-16, the Americans went with controlled differential steering instead, which is more effective and more reliable than track-warp steering. The fact that your carrier moves slightly with pressure on the wheel means that neither the steering linkages nor the crosstube are locked up.