Need some design help

[Gary_in_Indiana]

I'm looking to design and build something portable that would allow a standard trailer hitch/ball to be added temporarily to a semi tractor. Here's the tough part. I can't tell you what the tractor will be by year, make or model. It could be anything. This hitch assembly needs to be able to be installed by one person with simple hand tools. It needs to be strong enough to be able to pull a two ton load.

Currently, when I buy a semi tractor out of town/state I have to send two drivers and a vehicle to go get it. If I were able to come up with a universal way to attach a hitch I could send one driver with the temporary hitch and a tow dolly. Once there, the driver could attach the hitch, hook up the dolly, load the car on the dolly and drive the truck back towing the car on the dolly. I'd avoid the expense and hassle of sending a second driver.

Well, that's what I need and why. I see a lot of set ups like this for one truck to be used over and over on that truck and they're just welded on permanently. The challenge here, as I see it, is coming up with something which can be used universally and can be installed by one person safely and securely with simple hand tools.

 

[Thomas]

Maybe the folks that move moblie homes etc.. have such a setup your seeking and you could take a peek /w3tcompact/icons/eyes.gif for in these parts the caution or chase car hook behind the tractor than tow back.

 

[hazmat]

Rig something up on the tow dolly so that you can attach it directly to the fifth wheel. You could make it so that it breaks down for easy storage. IE something that pins / bolts together. I am assuming you are towing the tow dolley out with the car? Or is it a pickup? Pickup would make carrying the extra parts easier.

 

[Anonymous Poster]

3 pieces of 4" square tubing with a 5th wheel pin and 10" plate on one end, and an inverted U shackle and trailer ball on the other end in a stretched Z configuration should do it.
You could make it to fold, or to be pinned together.
Since you'll be towing a car with a road tractor, braking sholdn't be a problem, so you won't need to make it up to allow the tow dolly to self brake.
You can even make the piece with the 5th wheel pin telescopic to accomodate tandems and western spread tractors.

 

[beenthere]

Would ramps and rails designed to permit the vehicle to be driven onto the tractor, straddling the 5th wheel, then strapped down work in any way, shape or form? Possibly an investment at the pick-up end in a couple of timbers (6x6 comes to mind) and planks, with some tie-down straps to just carry the vehicle back home could be considered.

 

[Gary_in_Indiana]

Thomas, the problem with that is that those folks have a permanent mount system configured to their toter. I need something that is universal and temporary.

 

[Gary_in_Indiana]

Hazmat,

I like using the fifth wheel with a couple concerns. One is that the fifth wheel, the hitch ball/coupler connection and the platform on the dolly are all three pivot points. I'd like to eliminate the third one at the fifth wheel. Two is bad enough.

Here's a thought I had. I could run tube stock from the fifth wheel back (in one or two pieces) with a drop piece on the back end to accomodate the ball. Then I could place a piece at 90 degrees from that to rest across the frame rail to keep everything above them. Then, to eliminate the pivot at the fifth wheel, I could place another piece at the same 90 degrees spaced slightly below the first one to fit under the frame rail flanges. That piece would keep the ball from coming up and, with some type of expansion feature, would eliminate the fifth wheel as a pivot point and lock out any lateral motion.

What do you think of that?

 

[Anonymous Poster]

Gary, I'm sticking to the stretched Z from the 5th wheel.
By using the Z, you only have one pivot point, at the 5th wheel, cause the Z becomes a toung extension from the tow dolly.
I have a trailer we extend the toung on by the same method for long tows.

 

[bgott]

Send the driver on a Grayhound and give him cab fare to get to the tractor from the station. The driver might not like that, though. I took a hound from California to Colorado to repo a car one time and it really kind of sucked.

 

[Gary_in_Indiana]

It took me a while to figure out your idea and now I think I have it. If I'm right, you're talking about running from the fifth wheel back then down 90 degrees +/- to hitch height then back 90 degrees +/- to be fixed to the dolly tongue so as all to be essentially a dolly tongue extension. Do I have that right?

My concern with something like that is that it's an awful long extension and would be subjected to a lot of bouncing, twisting and torquing. I'm not saying it wouldn't work. It just seems like a lot to ask of tubing.