I finally remembered to ask this question about trucks or trailers that lift their axles

Agreed, one of my spread axle trailers has the Hendrickson Smart lift system... Pretty awesome.

.

 

That's a real nice setup. I've always wanted one too but the added weight has me rethinking it.

 

It's actually pretty light, like 85lbs if I remember right. Pretty simplistic i was surprised

 

In the gasoline business out west a lot of companies run truck and trailers. The set is much easier to get around and you can load more. Some states allow for oversized loads so your see all kinds of different combinations. I drove a truck and trailer that was an oversized permitted load, truck had 4 axles (one was a drop axle), and trailer was also 4 axles. One the truck we had a drop axle to keep as much weight off the steer. We loaded right up to the mark just about every time. 3250 gal in one compartment and 1550 gal in the rear. That kept us right at the proper weight. When loaded the drop axle went down, when empty the drop was up. All the controls to move it up or down was done on the outside by toggle switch mounted just behind the cab. I was told (was told) that the law stated" the switch to control the movement of a drop axle must be on the outside". It did not matter to me, I just got used to it. My picture shown is not the truck I drove, you can see it if you search but not much different just an added axle here and there.

 

No. It's a dead axle