Why is it better to have the tandems slid forward when alleydocking?

I'm old and not trying to be smart. Although I only drive a couple days a month now, I've been driving for decades and it doesn't matter to me where the axles are when backing into a dock. That said, if the customer wants the tandems back while docked, I do it when I open the doors.

Perhaps a little too much thinking going on.

 

I prefer tandems all the way back/rear
Don't have those issues any more, In the tanker world there's no sliding tandems

 

This is where I think you went wrong. I disagree with the other driver.

Two extremes, but have you ever backed a 28' pup trailer . . . or a 53' stretch Tri-axle step (or an RGN for that matter) ??

The shorter trailer turns much quicker, so you don't need much room in front of you.

The longer trailer (tandems at the rear) will take more room in front of you, and react slower than the short pup trailer.

Tailswing? Is an issue with the trailer tandems forward, and if you keep 'following' and turn too tight, then you've got multiple issues and have to reposition, pull up, or you'll be snaking after the trailer trying to catch it, and be well off your intended mark.

 

Side note - over the years, I think the most fender benders I've seen at docks and truck stops - are due to tail swing, typically catching the truck to the right (passenger side) of the one backing in, or pulling out.

 

There is only one type of tail swing. Tandems slid forward, backing or going forward = tail swing. Typically I would perfer the tandems to the rear, less work. If you are pulling forward for a pull up, if there is nothing next to you, who cares about tail swing. I think your question about being worried about tail swing while moving in reverse is rather silly. Not too sure about "worried" but if you are backing in between 2 trucks or trailers at an angle, you sure better be aware or "concerned" about tail swing otherwise there goes someones mirrors or fender or the hinges on your doors.

 

I'm a yard dog. I work at a facility that requires tandems all the way back, so I have been doing this 6 years. The advantage to having them all the way back is you don't have to worry about a lot of trailer swing in the back. When you back up with the tandems forward the back of the trailer has to swing a lot to get straight.

Also, in the same instance, a trailer with the tandems forward bends a lot quicker and if you over correct the passenger side will kick out quicker putting you in a situation where you will hit the trailer next to you. With the tandems back it bends a lot slower so you have more time to correct that. You can see the trailer bending slower giving you more time to stop and correct.

 

With trailer tandems forward you need less overall empty space in front of the "parked in the dock" position. But with tandems anywhere forward of the farthest-to-rear position you have tail swing of the trailer rear to worry about. If you have all the room any driver could ask for, it's easier and safer to slide tandems to the most rearward position. I learned how to back with my tandems set for weight distribution, not ease of backing. I learned to drive and back before air-release tandems were available. Because of that I learned to not slide my tandems unless it was required because any trailer that was older than 6 months would likely have some difficulty sliding the trailer tandems.