oday’s larger travel trailers and fifth wheels are truly houses on wheels. They offer all the amenities needed to provide a comfortable place to stay during a weekend getaway, going on a long vacation or even being used for extended stays. The downside is these RVs take a constant pounding when being towed over rough roads, which are all too common across the country — and those hits from the stiff solid-axle trailer suspensions take a heavy toll on the trailer and everything inside.
“The (OEM) leaf-spring/solid-axle suspension system under RV trailers really isn’t good enough to protect the house on wheels from damage and road shock,” said Jack Enfield, sales and marketing manager at MORryde International, an industry leader in RV suspension systems.
As Enfield pointed out, unlike the abundance of suspension travel afforded in the pickup trucks doing the towing, the typical RV trailer leaf-spring suspension only has about 2 inches of total travel. When the trailer is loaded up, that suspension travel is limited to about an inch.
That’s like having no suspension at all to soften the hits.
“That’s why we developed our Independent Suspension (IS),” said Enfield, who is an avid RVer himself. “Our IS system provides more than five inches of suspension travel, which significantly reduces that road shock and the damage it does to the trailer and its contents. The rubber shear springs in our IS system also reduce road-induced vibration, which takes its toll on everything inside the trailer.”
So how does road shock affect the trailer? You feel it. You see it.
It could be things that are moving around. It could be chairs tipped over. Doors and compartments open. It could be breaking things. It could also mean seeing uneven tire wear, loose screws and bolts, cabinets and counter tops separating, TV wall mounts torn loose, cracks in sidewalls and doors not opening or closing properly.
“We’ve heard all kinds of extremes,” added Enfield. “On rear-kitchen fifth wheels with leaf-sprung axles, customers have complained they find broken things all over the place. You can also feel the road shock in the truck when you’re towing the trailer and go over a bridge, an expansion joint, crossing railroad tracks, hitting the chuck hole. And you feel the hits twice — once with the truck and once with the trailer.”
When a trailer suspension takes a hit, so does the entire RV inside and out. That means the structural components that make up the walls, floor and roof are being subjected to the same G-forces and constant pounding reverberating upward from the tires through the leaf springs and into the chassis. As the road miles add up, so does the damage — seen and unseen — being done inside the trailer.
MORryde’s Solution to a Smoother Trailer Ride
Elkhart, Indiana-based MORryde has been in the RV suspension business since 1966, and its RV Independent Suspension was introduced back in the mid-’90s and used by OEMs under mainly high-end travel trailers and fifth wheels. But in the past 15 years RVers’ requests to get the IS system installed under their leaf-spring/solid axle trailers resulted in the company offering custom-built IS axle assemblies and installation for retro-fitting to existing rigs.
The beauty of an independent suspension is the independent wheel action, meaning that the left and right tires are not connected together. So when the left tire hits a bump or pot hole, the right tire doesn’t know it, and vice versa. Combine that independent wheel action with five and a half inches of travel, along with a heavy-duty hydraulic shock absorber at each wheel to keep that tire from bouncing, those rough sections of road go by almost unnoticed.
Between the IS system and disc brake option, Enfield told RV Enthusiast that RVers toting a heavy fifth wheel travel trailer or toy hauler will see and feel the huge improvement in ride, handling and braking, as well as significantly reducing the chance of damage to the trailer and its contents.
“We see a lot of toy hauler owners, in particular, making the conversion because they’ve got their toy back there and 10 to 12 feet of overhang behind the rear axle. When you’ve got your ATVs, your motorcycle back there, those solid axles act almost like a springboard or a diving board when the tires hit rough spots in the road. Our IS suspension is able to protect their toys much, much better.”
The Cost of an IS Conversion
The MORryde IS trailer axle conversion has gained a lot of interest over the past few years as road and highway surfaces seem to continue on a decline. The most popular trailers getting the IS conversion are tandem- and triple-axle models with the 7,000-8,000-pound leaf-spring/solid axle setups, according to Enfield.
“The sweet spot is trailers with 7,000- and 8,000-pound axles,” said Enfield. “But we can do 9,000-pound axles. We can also do 6,000-pound axles. Once you get lighter than 6,000-pound axles, though, I’m not sure it makes the most sense for the return on the investment.”
Converting from solid axle/leaf spring suspension to the MORryde IS ranges from $5,000 to $12,000 for tandem-axle trailers, depending on the location where the conversion is being done and whether or not the MORryde axles have the disc brakes. (The differences in price have to do with the size of the system, shipping costs and local labor rates.) A tandem-axle conversion takes about 30 hours in labor.
The upside of the investment making the independent suspension axle conversion — beyond the improved ride — is on the re-sale/trade-in side. Most RV trailer owners should be able to recoup a good portion of the expense when they move on from their trailer.
“As long as they let the buyer or sales person at the RV dealership know the trailer has the MORryde IS suspension, that’s definitely an added value because a unit with our independent suspension system will be in better shape than one without. And if they talk about the features and the disc brake option, the owner can tell them, ‘Hey, this is what it costs if you wanted to go get this done.’”
RVers who want the IS axle conversion must have it done at MORryde, or at one of the company’s two authorized installers: New Horizons RV in Junction City, Kansas, or at Henderson’s Line-Up in Grants Pass, Oregon. It’s easy to make an appointment at MORryde’s corporate facility in Indiana or the two other locations.
Henderson’s Line-Up Brake & RV converts about 24 trailers a year to the MORryde IS system at its facility in Grants Pass, Oregon. We happened to be there when a customer’s Grand Design Solitude ST310GK fifth wheel was dropped off to have the factory solid-axle/leaf spring (with electric brakes) suspension upgraded to the 7K IS with Kodiak disc brake option, and followed the process. It’s an involved swap — but well worth it.
