Bus with a 5th wheel

[Dale]

Hi first time caller, My names Dale.

I have a few questions. First I’ve got 68 passenger bus, I want to apply a 5th wheel to it, is it possible? Without losing too much floor space. I was considering on buying another axle and put it about 5 ft from the end of the bus, for support of the 5th wheel. Like I said I don’t want to lose too much floor space. I know I’m going to have to lose 6 ft. But I don’t want to start cutting down the frame. 

[travelinbob]

I think you'll be too long for travel unless the 5th wheel is a mighty short one.

[Second Chance]

There is a piece of equipment called the Automated Safety Hitch that does just what you describe. However, as mentioned, you would be over the legal length in many states and that bus won't have the power to pull a fifth wheel of any size up any kind of a grade.

Rob

[TXiceman]

Like noted, what will your total length be when completed.  Some state are 55', some 65' and some longer for total overall length.  Another issue is the tag axle and scrubbing in a turn.  Are you going to lift the axle in turns?

 

Ken

Edited April 1, 2021 by TXiceman

[Dale]

I guess I forgot to mention I’m from Saskatchewan Canada 

[kb0zke]

As they say, you can make anything fly if you throw enough money at it.

Many school buses are geared for in-town routes, so they aren't really able to go all that fast. Also, even though they are built on a medium-duty truck chassis, they rarely are loaded anywhere near GVWR, so the engine seems to have enough power, but it really doesn't for what you are proposing.

Remember that a fifth wheel needs the hitch pretty much over the rear axle, You will want to make sure that you have plenty of room between the back of the bus and the front of the trailer. If you already have the trailer, you can measure from the pin to the body to get an idea of what you need. Deduct whatever you think is a reasonable clearance and that is the radius from the hitch to the end of the bus. Example: you decide that six feet gives you the safety margin you want. Draw an arc with a six foot radius from directly over the center of the rear axle, and everything outside of that arc has to go.

Before you start cutting, though, check the rear axle weight capacity and compare it to the actual weight on it now. Yes, you are going to remove some of that weight when you start cutting, but at least you will have a starting point. Remember that 20-25% of the GVWR of the 5'er will be on the pin, which means on the rear axle. Add to that the weight of the hitch assembly, and you are starting to get closer to what will actually have to be carried there.

Now the question everyone is wondering about: Why do you want to do this? Reading between the lines, it sounds like you want to have a fairly large enclosed space in the tow vehicle. That might imply that you will be carrying quite a bit of weight there. You might want to start adding up the estimated weight of what will be inside the bus.

Adding a tag axle also adds weight and may not actually change the weight you can legally carry. Unless you go through all of the engineering work and get your vehicle recertified with a higher GVWR, I think you will be stuck with whatever it left the factory with.

I've spent a fair amount of electrons on the issue of weight. The length is easy: check your laws there. I don't know about Canada, but here in the US it doesn't matter what the maximum legal length is in your home State, you have to follow the length limits in whatever State you are in. Our MH and towed are just under 60' overall length. That's fine for most of our travels, but when we go out east we may not be able to travel that way, in which case we'll unhook the car and Jo Ann will drive it. Can't do that with a towable.

[lappir]

Try to find a couple of toys that can be a close match to your project and run them around  a bit. You may find the extreme wheel base of the bus and a 5th wheel trailer don't really work all that well. Yes there are LONG semi tractors that are pulling equally long trailers, but most of them don't get much off the Interstate highway system. 

As it's been said, you can do almost anything if you toss enough money at it and in the end if that's your plan, best of luck. 

A person who used to be active on the HDT section used models when building his garage on the back of his HDT. You might be able to find his work with a bit of searching. I'll try to remember his screen name and add it later. 

 

Rod