Well lets roll back the clock a moment to Granddad's day.

New Idea came out with a brilliant 4 wheel steer wagon gear. In those days it often meant negotiating through narrow corn cribs crowding tight to one side to unload.

As you exited the building you steered towards the middle again which promptly steered the rear of the wagon into the crib wall.

Many an upset farmer cursed such a dumb idea on a wagon running gear.

Now let us fast forward to to day where wide open buildings and large doors allow for backing something straight in or driving straight on through.

I have no personal experience with the new or old designs but can see advantages and disadvantages based on situations and usage.

For me "here" where everything is an obstacle course in tight cramped buildings I don't think a 4 wheel steer  would suit my needs.

Are the newer models able to be locked out or do they 4 wheel steer all the time ?

For my needs which are surely different and smaller than the OP described a nice used J&M HT874 cart is what I went with.

Extension tongue,flip over adjustable mounts for corn head or platform,ratchet tie down straps and safety lights.

Edit: My primary reason for purchase of this model was a long history of my own positive experiences with J&M products and a history of tracking well on the road without swaying or whipping side to side.

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