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RV's! 4

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XR250

XR250

Structural
Jan 30, 2013
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I don't understand this industry.
Seems like one company, Lippert, makes the majority of the frames for Rv's in the USA. There are so many incidents of these frames cracking. Fifth wheel frames cracking inside the front of the trailer. Regular tow behinds cracking if you use a weight distributing hitch and go down a bumpy road. Spring shackles bending and pulling off.
Lippert claims they build the frames to the manufacturers specs. Manufacturers claim it is Lippert's problem but they spec the lightest weight frames they can so they don't overload the axles and can fit more amenities inside.
Do any of these companies employ structural engineers for the design? Most of these large RV's are always pushed up against their axle and tire ratings. Can't imagine this is safe.
Are there any ASTM or SAE standards for any of this. Does it ever get enforced?
OK, that is my rant for the morning.
 
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The main problem is they are excluded from laws that cover cars when it comes to defects. The warranty is "did it make it off the lot - it's all yours."

Watch any of Steve Lehto's videos on RVs for a lawyer's take. He specializes in lemon law suits, but lemon laws do not apply to RVs and he won't touch an RV related suit with a lengthy stick.

 
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AFAIK the only people in the RV industry to ever truly suffer for their actions was Goodyear, who sold tires to it. They make a truck tire for low-range vehicles that works perfectly; got to move furniture or a bunch of lumber 20 miles? Great. They can do that until the rubber rots. Then some bean-bag said "why not corner the RV market? Unlike delivery trucks,

RVs will go 500 miles in one shot at 70 mph (or so, it's been a while; check the lawsuit for details) and that is too much for the tires to take and they overheat and fail.

NHTSA’s letter said Goodyear’s G159 tire, size 275/70R22.5, was introduced in 1996 for start-and-stop urban delivery vehicles and sold for roads with a maximum speed limit of 65 mph (104.6 kilometers per hour), as all roads were in 1996.

Later they were used as original equipment tires on large motorhomes that typically travel long distances on highways. Such use can increase the tire temperature and deteriorate its performance and life, the letter said.

In 2007, a Goodyear engineer testified in a court case that operating heavy truck tires above 200 degrees Fahrenheit could cause tread separation. Yet in August of 1996, Goodyear tests of the recalled tires found temperatures “well in excess of 200 degrees F at 50 mph,” the letter said.

Goodyear started getting injury claims in 1998 as some states raised freeway speed limits to 75 mph. It also received death claims every year from 2002 through 2006, the letter stated.
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Longer read:
 
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My wife has seen the replacement parts side of the RV industry and tells me we will never own one. They are meant to move down the road frequently. However, as you stated, they use the lightest frame and chassis possible to add more features. They are not designed to protect occupants during an impact. So, when your drunk neighbor at the campground plows into your home away from home, good luck.
 
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The challenge with RV's is that they are driven by amateur drivers. Some are good, some are not. The bad ones put the RV into situations they should not be put into. Think driving over curbs and flexing the chassis with the steering at full lock when one gets stuck in a parking lot.
 
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That might have something to do with it but in general most are just total POS. (at least in the US anyhow)
 
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See also horses.

Chassis cab manufacturers have handbooks and design manuals for aftermarket mods, specifying loads and cg location and so on. The problem is that if you followed them then your competitor will be able to offer a better specced RV for the same cost and weight by ignoring them. It's just the usual race to the bottom. Having been through this with houses there is always an option to pay for a better builder, and after 10 years the difference will show.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
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This is also another example of the great misunderstanding of what supply and demand actually means. There is not high demand for RV's so it costs more to provide the same level of quality as more mass produced vehicles.

Finally, people buying RV's are typically older and don't really need them to last very long.
 
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Tugboateng said:
Finally, people buying RV's are typically older and don't really need them to last very long.
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That's ageism Tug!!

I never really thought about them being built specially, but it seems so.

The smaller ones sit on truck chassis, but the bigger ones look pretty flimsy given the size and weight of them.

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The ones with the truck chassis at least will have decent frames. What is sitting on them is shit though.
My OP was regarding pull-behinds mostly.
 
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You don't see many if any fifth wheel type caravans in the UK or Europe. You just wouldn't be able to drive them down the country roads.

Most are single or double axle towed behind "normal" cars with a ball and socket hitch. Probably about half the size of what you find in the US and Canada.

Speed is supposed to be limited to 50mph. The frames of most of those are pretty flimsy alright.
And its common to seem them on the side of the road completely minus one wheel or where the wheel is at a rather strange angle

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Finally, people buying RV's are typically older and don't really need them to last very long.
Click to expand...

Aside from the ageism, I think that's erroneous from the buyer's perspective. If, and that's a big if, I were to buy an RV, I'd have visions of driving same through my go-go and slo-go years, so that's in my mind at least 20 years. Now, it may be true that I wouldn't actually "need" that long a lifespan for the RV, and maybe the manufacturer knows this, but I'd certainly be going in with that longevity mindset, particularly since it's fairly significant investment, so I better damn well see reviews that say their RVs lasted and survived multiple cross country road trips. I will say that I'm troubled by the "conveniences" of "Transformer"-like expansion cubbies and other mechanizations, since they seem like monster reliability pitfalls and repair bills, but driving around something that can expand at will seems pretty cool.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
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Some of those trailers are about the size of my house...

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The only exception that I know of is Air Stream.
They build a steel frame and coat it.
Then they build and Al shell.
Then they build in the interior.
This means that everything can be repaired/replaced.
Yes, they are expensive, but many 40yr old Air Streams are still very serviceable.

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P.E. Metallurgy, consulting work welcomed
 
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