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| Construction- Frames and Floors |
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It's easy to walk into a fifthwheel and tell whether the upholstery is of good quality or whether the cabinets are well constructed. But what about the things you can't see? These "invisible features" are really the most important aspects of your new fifthwheel, yet most people don't even know the right questions to ask to find out whether or not they are getting a good product. Before purchasing a fifthwheel, especially one with a slide-out, you better find out about the construction of two major components:
1) The Chassis Frame
2) The Main Floor
If components are not up to snuff, long term slide-out fit and good towability are probably not in your future. That is why so many of our RT specifications have to do with these vital fifthwheel components. Lets take a look at them and see why each is so important. |
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The Frame
The main floor hanging after the main axle position is a cantilever structure, meaning it is being partly supported by the walls themselves (sort of the opposite of a house). If you have a fifthwheel with a slide-out, then you have a big rectangular hole in the side of one of your walls. If your floor should over flex and flap up and down a little bit when you are going down the road, then that big hole may parallelogram, or go out of square. When this happens the rectangle may not return to having 90 degree corners, in which case the gaskets around the slide-out would not retain a proper fit, meaning leaks could occur.
Therefore it is important to design and build a fifthwheel with a floor that doesn't tend to flap up and down as you travel down the road.To insure that the floor doesn't over-flex you have to start with the main chassis |
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| The gooseneck. |
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frame. Just like when building a home, if you have a good foundation then you can be confident that the walls will be true. Many of today's RV manufactures still use the same steel chassis frame for their slide-out models as they did for their earlier non-slideout models, which was often a 2" by 6" or 2" by 8" rectangular tube.
As long as you didn't cut a big hole in the side of the wall, this frame was fine, but with a major part of the wall section cut out for a slide-out room they are lacking a strong enough wall to hold the floor up. Remember we talked about the wall helping to support the floor? RV walls act as a large bridge girder and literally hold the floor up. If you cut a big hole in the wall for a slide-out, what is going to keep the floor from flexing up and down? The answer is that the floor and chassis have to take care of themselves. The manufacturers who have not correctly redesigned their chassis frame and floor for slide-outs have had many slide-out fit and gasketing problems. If you have shopped for fifthwheels and talked to owners of slide-outs not correctly re-designed, then you have undoubtedly heard several horror stories about non-fitting slide-outs that refused to slide either in or out, or if they did, didn't fit. |
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This is why our RT specification calls for a 12" Junior "I" beam frame with special gusseting at the "goose neck" transition from the main floor to the bedroom level. An "I" beam is the best available structure to not only handle long span cantilever flex, but also twisting forces caused by torsional loads as you travel down rough and uneven roads. We use an 18" steel web section (distance from the axle mounting pads to the floor overhead) at our main axle fastening point carry through section in the center of the frame. This is the point where the greatest bending moments concentrate in the lower chassis. 18" yields a fantastic amount of strength, and that is just what we are looking for if we don't want the frame or floor to over flex.
Weekenders will often use their fifth wheels for no more than two or three weekends per month, and when they do take them out, a long trip is 200 miles. Fill timing is a whole different ball game. |
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The I-beam.
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The much larger number of miles traveled and the higher frequency of travel means that full timers' needs are very different than the average weekender. Manufacturing processes that might be ok for a what is nothing more than a glorified toy are just not adequate for the needs of serious users. Full time RVing means owning equipment that is durable enough to meet those needs. The frame of your RV is the foundation on which every other component is built. Make sure yours is stong enough to do the job. |
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| The infamous cars. |
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Built to last
In this day and age of "throw-away" products, it's hard for some of the young people around us to understand that "built in obsolescense" is not a term some of us older folks really care for. It used to be that products were made to be repaired as they aged, owned for years and then passed to the next generation. Most products were fixable, and not only that, they were designed to be fixed. You could buy spare parts. They were supposed to last. Which brings me to a little story about my own vehicles, and my own tendancy to hold on to them for a long time, keeping them alive and well. They are part of the family after all. |
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I genuinely feel that some products are good they day they are made and some aren't. As Ben Franklin said, "the quality remains long after the price is forgotten" On this page is a picture of two good products that have served me well over the years. One is my 1973 Volvo (my new car . . . I guess I get frugalness from my father) has over 300,000 miles, has it's original engine, every thing still fits and it drives every day. The other is my 1979 Chevy Diesel pickup which has at least 1/2 million miles on it. My son has promised me that when I die he will put me in it, place it on a barge, light it a-fire, and have a Viking funeral. That truck will most likely last longer than I will. Oh, yes my wife has a newer BMW and she hates my old car and truck.
We hope our products will be as durable as these two (which is what the RT Spec. is all about), but without putting time and money into our fifthwheels in places that they won't show right away, they just wouldn't.
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