Pup trailers

[Skeans1]

Does the PUP trailer I posted have a converter dolly? It appears to be a permanent front axle. Probably has no bearing on the question, just thinking out loud

It has one, there’s a locking pin to center the dolly for backing up.

 

[3 Horse Ranch]

Does the PUP trailer I posted have a converter dolly? It appears to be a permanent front axle. Probably has no bearing on the question, just thinking out loud

I looked at the photos and didn't see any landing gear so I would assume that trailer has a turntable. It bears a resemblance to the transfer trailer chassis I mentioned above but without the tandem rear axles they have,

 

[3 Horse Ranch]

I cannot tell for sure but you may be right. The fifth wheel on some dollies sit real high and would be obvious. Others, the trailer rides more level.

None of ours had a lock for backing, and there wasn't a locking pin on the flatbed trailer I pulled years ago for a lumber yard.
The last dump pup trailer I pulled had a turntable lock. It was the only 4 axle pup I ever pulled that had a turntable. It could be backed unlocked, but it wasn't easy.

 

[Renze]

A wagon type trailer, with a roller slew bearing above the front axle, is the standard outfit for container transport in Europe as it is insensitive to incorrect weight distribution, and can be transferred without landing gear back and front.

Especially with a high center of gravity and little tongue weight of mid axle trailers, the back end of the truck is pushed around. You dont have that with a slew.

 

[Hay Dude]

So you straighten your truck/trailer, get out of the cab, walk back to the trailer and throw a lever to lock the front dolly for backing, correct?

 

[Hay Dude]

A wagon type trailer, with a roller slew bearing above the front axle, is the standard outfit for container transport in Europe as it is insensitive to incorrect weight distribution, and can be transferred without landing gear back and front.

Especially with a high center of gravity and little tongue weight of mid axle trailers, the back end of the truck is pushed around. You dont have that with a slew.

Hah, I thought the container would fall to the ground when he pulled away! Thats pretty sophisticated. Driver made it look easy.

 

[tree grower]

In the northeast pup trailers are most commonly used with log trucks, but they are not 'four-wheel' trailers. They are tandem axles with tongue weight on the truck.

 

[Renze]

So you straighten your truck/trailer, get out of the cab, walk back to the trailer and throw a lever to lock the front dolly for backing, correct?

Off course not, its a waste of tires, and the chassis needs to be a lot stronger to withstand the twisting.

With the trucms trailer coupler reasonably far behind the tandem turn center, the trailer reacts much more direct to steering movements so its easier to back up than with a farm tractor with the drawbar 2 feet behind the rear axle.

 

[ovrszd]

Off course not, its a waste of tires, and the chassis needs to be a lot stronger to withstand the twisting.

That's the intent. Lock the turntable for easy backing. Our military has many varieties of these and they work well.

 

[Hay Dude]

Off course not, its a waste of tires, and the chassis needs to be a lot stronger to withstand the twisting.

With the trucms trailer coupler reasonably far behind the tandem turn center, the trailer reacts much more direct to steering movements so its easier to back up than with a farm tractor with the drawbar 2 feet behind the rear axle.

Not sure we are talking about the same thing.
The dolly steers during normal driving, but require locking for reversing, right?

I didnt know if there was an air lock from cab, or a manual pin/lever set up.