everything shakes loose

[ZachO]

Originally Posted by DavidG

ZachO, I think almost any motorhome suspension beats most little one axle travel trailers like Scamps. And trailers handle better when they are pretty loaded, not running empty. And BYW, was some of your motorhome handling experience with your mini Toyota Chinook ? Mine handled nicely if not overloaded. Happy Trails ! David in Fresno and Sonora

Yep, it's the Chinook I'm talking about. Mine drove great, nice and straight and smooth down the highway. But on a dirt road, I could really hear the cabinets rattling and fiberglass body creaking and cracking against the truck. It was the washboard, the potholes, and in extreme cases the angles the Chinook would be at that were twisting the body. I didn't shy away from rough dirt roads and I had a couple times of being stuck to show for it. One time took me a good 3 hours of digging and jacking the thing up to get unstuck. Second time, luckily, someone came along before I even had a chance to get the jack out and towed me out. So yeah, knowing how much a camper got beat up with passenger vehicle suspension, I figure it's much worse with trailer suspension.

I agree with the other posts, going faster is not the answer to washboard in a camp trailer. In a passenger vehicle, yes.

[stevebaz]

Hook up your trailer to your car. Do not put down any supports. Get a couple of people on the back bumper and have them try to bounce the trailer. if it won't bounce while tied to the car with no supports it has no ability to dampen the shock load of traveling down the road. Just make sure your trailer is fully hitched when you do this test you don't want to lift a hitch and go for an unexpected ride. Note whether the movement is a in the suspension or just in the tires or a little of both. No one builds real offroad trailers with rubber mounted torsion axles. None of the light weight torsion axle molded egg fiberglass trailers were designed for off road travel. Ask any of the Manufacturers if they will warranty any of their trailers used off road.

[Civilguy]

Originally Posted by stevebaz

Hook up your trailer to your car. Do not put down any supports. Get a couple of people on the back bumper and have them try to bounce the trailer. if it won't bounce while tied to the car with no supports it has no ability to dampen the shock load of traveling down the road.

So if I am getting this right, what you are saying to pay close attention to whether the torsion axle rubber is flexible and providing some "spring" or if it appears to be dried out and basically doesn't move much. This sounds like a sensible approach. Is my understanding correct?

It seems that keeping the tire air pressure maximized while doing this test might eliminate some of the "spring" in the tires so that one can focus on watching whether the axle motion is "lively" or "dead".

[floyd]

Torsion Axles do not wear out without showing tire wear due to excessive negative camber.

A "bouncy" trailer is more likely due to a light load on a good axle or an over rated tire, than it is to a weak or worn axle... Ever tow an empty utility trailer or an empty car dolly?



The only real cure for a bad road is a different route.

[redbarron55]

Over rated axles are common and too high a rating the axle is too stiff to absorb the bumps.
Too stiff tire = the same.
Just right is ..... just right
I had my Flexiride manufactured for 3000 lbs instead of 3500 for my 2800 + lb Scamp for this reason.
The axles and mechanical bits are the same, but the amount of rubber in the spring part to make it more compliant.
To control the bounce the excess movement needs to be converted into heat, usually by shock absorbers.
The rubber torsion axles do convert some of the bounce into heat better than leaf springs, but the answer to washboard roads is a different route.
Unfortunately most of the time there is no choice.
That section of I 10 through Louisiana comes to mind.

[Civilguy]

Originally Posted by floyd

Torsion Axles do not wear out without showing tire wear due to excessive negative camber.

A "bouncy" trailer is more likely due to a light load on a good axle or an over rated tire, than it is to a weak or worn axle... Ever tow an empty utility trailer or an empty car dolly?

The only real cure for a bad road is a different route.

Floyd,

I'm with you on the bouncy, light-load part.

However, at this point I can only be hopeful that one day I will actually be putting enough miles on the trailer so that I will see tire wear when the rubber in our axle hardens.

[David Tilston]

Originally Posted by floyd

Torsion Axles do not wear out without showing tire wear due to excessive negative camber.

I have an axle that it seems like the rubber has turned to cement. No excessive negative camber, also no suspension, other then the tires.

[ehoepner]

Try having the tires balanced. Had one tire once that was really out of balance. The tire company put a very large balance weight on it to get it balanced. Everything was much better after that.

[Glenn Baglo]

I think we are talking about washboard roads, where balanced wheels will make little difference.

[Raspy]

Originally Posted by ehoepner

Try having the tires balanced. Had one tire once that was really out of balance. The tire company put a very large balance weight on it to get it balanced. Everything was much better after that.

Please read earlier posts about the frequency of washboard vs the frequency of unbalanced tires. The OP was talking about washboard. But yes, all trailer tires should be balanced.

[David Tilston]

Originally Posted by Raspy

Please read earlier posts about the frequency of washboard vs the frequency of unbalanced tires. The OP was talking about washboard. But yes, all trailer tires should be balanced.

Though some places will look at you weird if you ask to have your trailer tires balanced. I was once told, "we never balance trailer tires".

[ZachO]

That photo Glen posted makes me want to go out and take of photo of some of the washboard around here.

Makes me think of Crocodile Dundee (something which, believe me, I haven't done in a long time). "You call that washboard?"

[Civilguy]

Originally Posted by ZachO

"You call that washboard?"

Oh, we all know that Glenn is something of an urban sophisticate. ; )

[Raspy]

Originally Posted by ZachO

That photo Glen posted makes me want to go out and take of photo of some of the washboard around here.

Makes me think of Crocodile Dundee (something which, believe me, I haven't done in a long time). "You call that washboard?"

No kidding. And I remember that line with the big knife.

You call that washboard?!

I wish our washboard looked like that! In Death Valley that would be a smooth road. A person could fall asleep on that highway! I've seen table tops with more variation! I wish my glass windows were that flat!!! Well, that may be a bit of an exaggeration. Fortunately, I only exaggerate in the interest of truth.

[Glenn Baglo]

The trailer knows the truth.

[WizWid]

Originally Posted by Glenn Baglo

The trailer knows the truth.

The truth about the cheese?

[gordon2]

Originally Posted by Glenn Baglo

The trailer knows the truth.

Originally Posted by widgetwizard

The truth about the cheese?

Or perhaps the Shadow Knows. But in truth, I have given up on understanding Glenn's meaning most of the time. It's a frustrating exercise in futility.

Many of the things mentioned can contribute to this problem. Worn axle, wheel balance, road conditions, over or under loaded trailer, etc. The fact that a converter fell apart shows that it is an extreme situation so I suspect that many things are in play here as opposed to one primary issue.

[Yellow Boler]

I have a 1977 boler trailer that was quite bouncy. After replacing the tires it was night and day. It was way less bouncy. I also use the recommended manufacturer tire pressure of 26-28 psi. The manufacturer's recommended tire pressure is based on the weight of the trailer and has nothing to do with the maximum load rating the tire can take. You should only be using maximum tire pressure if your trailer recommended that pressure. Otherwise you will be too stiff for the weight of your trailer. A softer tire will absorb bumps better which is one reason why offroaders air their tires down. Under inflation can cause pre mature wearing of the side walls. Whereas over inflation causes pre mature wearing of the center line.

[Raspy]

Originally Posted by Glenn Baglo

The trailer knows the truth.

The mistake I made was thinking the first "n" was silent.

[Jon in AZ]

Originally Posted by Yellow Boler

I have a 1977 boler trailer that was quite bouncy. After replacing the tires it was night and day. It was way less bouncy. I also use the recommended manufacturer tire pressure of 26-28 psi. The manufacturer's recommended tire pressure is based on the weight of the trailer and has nothing to do with the maximum load rating the tire can take. You should only be using maximum tire pressure if your trailer recommended that pressure. Otherwise you will be too stiff for the weight of your trailer. A softer tire will absorb bumps better which is one reason why offroaders air their tires down. Under inflation can cause pre mature wearing of the side walls. Whereas over inflation causes pre mature wearing of the center line.

If that "recommended manufacturer tire pressure" came from Boler, it was based on different bias-ply trailer tires in use 40 years ago.

Whether or not to use the full sidewall pressure or to reduce pressure according to the actual load is very controversial here. But if you do run a lower pressure, (1) make sure you're using a current load-inflation chart from the manufacturer of your tire, and (2) make sure to leave a margin to account for variations in loading and unequal left-right balance.