Trailer Shocks Truck on Highway

[powerstroke444e]

You found the exact wrong trailer and truck lenght. I had a ford with 18' trailer that would do the same thing on jointed pavement.

 

[wkpoor]

I have experienced the same thing many times. I am guessing the stretch of highway you are talking about started 40 miles or so east of Indy on I-70. I can tell you I drive this road weekly, sometimes 3-4 times a week and its the trailer. I had the same thing happen with my buddies 14K dump behind my F-350. It seems to be worse with trailers that have the wheels aprox 60% of the way back from the tongue. Boat trailers, which I tow 90% of the time do not do it nearly as much. It think it has to do with the teeter/tooter effect. I towed a travel trailer down that road that weighed about 8K with my F-150 and it did the same thing. Made my innards feel like they were in a blender.

Chris you nailed it. East of Indy west bound side and around the south side of 465. Yep wheels 60% back.
As for the responses for the cushion hitches those are the wrong type for my problem. I have one like the first one and after a while the cushion takes a set and developes a dead space. Then you get clunking all the time. The second example is mostly for wagons and gravity beds that have no tongue weight but are heavy and will jerk to the truck for-aft. Only type that I can see helping are the ones like the Airlift that dampen the vertical ocsillations.

 

[Hematite]

I think what's happening is the road is driving a natural frequency of the vehicle and trailer as they oscillate around the hitch. It's a bit expensive, but I think a weight distributing hitch would solve the problem. You need to change the spring constant of the combined vehicle and trailer around the hitch, that should move the natural frequency away from the frequency that the road is driving. The weight distributing hitch significantly changes that spring constant, which is essentially zero right now. It has the added benefit of improving handling a bit and allowing a slightly higher tongue load.

Normally you could also change the mass of the system to get the same effect, but since you can only significantly change the mass of the trailer, and the trailer is mostly independent of the vehicle, that might not solve the problem.

I have experienced the bouncing from the trailer when empty. When loaded, I use a Reese high performance dual cam hitch system. The truck and trailer ride so smooth and stable with the Reese that the only way to believe it is to actually drive this combination. It is important that the system has been properly set up to get the most out of the system.

 

[Diamondpilot]

Chris you nailed it. East of Indy west bound side and around the south side of 465. Yep wheels 60% back.
As for the responses for the cushion hitches those are the wrong type for my problem. I have one like the first one and after a while the cushion takes a set and developes a dead space. Then you get clunking all the time. The second example is mostly for wagons and gravity beds that have no tongue weight but are heavy and will jerk to the truck for-aft. Only type that I can see helping are the ones like the Airlift that dampen the vertical ocsillations.

Its funny it was worse West Bound. It seems like I have experienced the worst ride East Bound. More tongue wight seems to help but there is no way to get around it totally. With the trailers wheels near the middle its gets the teeter/tooter effect. Like I said with most boat trailers have the wheels 85% of the way back it does not do it.

Chris

 

[wkpoor]

East bound was just so rough it couldn't set up the harmonics. And I mean dangerously rough. we saw a semi front wheels come off the ground in the r/h lane over a real bad bump.
About the only way I've settled this trailer down is to load right over the axle. I moved a car 4xs once always thinking more forward would solve it. Turns out I needed to move it back. The axles have to carry the weight not the tongue. So at least on this trailer I don't worry about tongue weight even though I imagine there is always at least 500-700lbs there all the time. It never sways.

 

[RobertN]

Exactly. There is a section of highway thru Sacramento that does the same to me. My old '89 F250 xcab long bed 4x4 AND my current '01 Dodge 2500 long bed xcab do the same. A trailer makes it worse.

My old Jeep CJ-5 did it just as bad; it was on the short side of the equation.

Pickups shorter than my truck, but longer than the old CJ5, don't do it so bad.

It is not so much an issue when I have the 5th wheel towing, I think because the kingpin is right over the axle.

I was on a trip in SoCal a few years ago with friends. We had to drive to Santa Barbara from Indio/Palm Springs. Not too bad till we go about 1/2 way from Palm Springs to LA. Then the expansion joints were AWEFUL. That was in my friends '00 Ford F250 crew cab short bed 4x4. My gut hurt for a week after that.

Makes me wonder; with all the technology we have now, can't they make a better road? I guess they probably could, at four times the cost

You found the exact wrong trailer and truck lenght. I had a ford with 18' trailer that would do the same thing on jointed pavement.

 

[flusher]

I really like the new trailer but have an issue that really raised its ugly head on my recent trip to Indy. On highways where expansion joints are under the pavement the trailer picks them up and sends nasty shocks waves at high frequency through the truck. So bad that after only a few miles it becomes un barrable. I assume the truck/trailer wheel base is close to 20' therefore just as one bump occurrs another comes right after therefore acting like a sign wave through the truck frame at a good rate. Enough to make your inerds feel like they are coming loose. Any thoughts on a remedy or what I'm doing wrong. Oh tried lowering tire pressure, doesn't really help but don't want that as a solution cuase when I get where I'm going and put a load on the trailer I'll have air back up. Its already been suggested slipper springs can do this.
OBTW....does the area around Indy have some of the worst roads in the midwest???

I assume your new trailer is bumper pull. I wonder how a gooseneck trailer the same length as yours would perform on that stretch of road.

I used to ride I-70 in STL from my place in the south city to the McDonnell Douglas plant at Lambert Int'l Airport on the north side of the metro area. That was a lousy stretch of road even in the late 1960s and 70s. Now I live in northern CA where the interstates out here are in poor shape also (CA is near the bottom of the list in road quality).

 

[RobertN]

I think all entry points to California should have their signs changed. They should read:
"Welcome to California"
"Caution: Rough Roads"

Now I live in northern CA where the interstates out here are in poor shape also (CA is near the bottom of the list in road quality).

 

[wkpoor]

I think all entry points to California should have their signs changed. They should read:
"Welcome to California"
"Caution: Rough Roads"

What tears em up??? All that sunshine hehehhee.
I know what tears our up....constant freezing and thawing.

 

[FlaDon]

I would nominate the strech of I-77 thru Beckly,WV for a rough road award. In fact, it's the section right in front of the WV Turnpike Auth. offices.

Towing the trailer light or loaded that section is bad. Leaving the LEH bars on when light can help some. And most bridges throughout the south seem to all be designed to bump at the joints due to curvature of the slump when concrete is poured and formed. Truck and trailer is up on the centers and down at the joint for each section.