dog wagging the tail

downtheroad wrote:
Here is a video that shows, "dog wagging the tail."

Click Here

WOW

Maybe this is not my issue because it doesn't seem as bad as the responses I'm getting.I don't pull a trailor this is a motorhome.I'm not sure if the feeling you get is similar but it does wander but not as bad as the posted are lmplying.

We drove past someone having this issue last summer. Scary stuff to witness. I can't believe they didn't pull off of the expressway. We managed to move over a lane and shot past them. No way did we want to be anywhere behind them.

The trailer has to have 60% of the weight in it in front of the axle or center of axles. That puts the weight on the towing vehicle which has to be within 4 inches of level to the trailer, by adjustment of the height of the hitch by making the suspension higher or lower to the point where the maximum tongue weight is not exceeded. If the weight in the trailer exceeds the design of the trailer and thus causes the trailer frame to twist, the beef up the frame or drop the weight. A welder can stiffen the frame up by using steel cross members that transfer the weight and eliminate the twisting. Of course if the hitch on the tow vehicle is not designed for the weight of the trailer then that vehicle needs to be replaced with a qualified set up for the trailer, or the existing tow vehicle can be modified by a welder and perhaps heavier suspension parts. Also tires can cause wag too if under inflated or being wrong tire for the weight. But 9 times out of ten it's the load in the trailer being to much to the rear, so just move the heavy stuff forward and down on the floor and not up in the cabinets, which causes top heavy wag.

If it's the F53 chassis, do the easy fix - front and rear. Makes a world of difference!

The sensation feels like how it feels to stand on the beach with a wave that comes in, then the water pressure changes as the water goes back out, catching you off guard and almost sweeping your feet out from under you.

It's a feeling of a force you weren't expecting or can tell where it's going.

Ever been on an airplane and think you are going straight but can't walk down the isle straight because the plane is really in a bank? Just doesn't make sense to your mind.

ford truck guy wrote:
I believe it is called "Tail wagging the dog" .. It is when you feel that you have to constantly correct the tow vehicle due to the trailer swaying too much behind you.The front of the trailer pushing and pushing the rear of the truck.

This can be caused by several different things including but not limited to--high winds...light pin weight , too heavy of a trailer period , and so on..
Like already stated , you will know when the tail is wagging the dog.. No doubt you will need to pull over and access what is going on....

AND to safely pull over with it wagging apply the trailer brakes ONLY hard until the wagging stops. Do not apply the prime mover brakes hard or the trailer may pass you. :(
A good rule of thumb is to have 10% of total trailer weight on the tongue. That is for tag alongs, not 5th wheels. 5th wheels can be 15-25% I believe----depends on the truck.

For me I had to constantly move the steering wheel back and forth to keep it going straight. As mentioned have you done the front and rear sway bar fix? You might need to add a trac bar to the rear end. After doing all these fixes I also found I as light on the front end. My front end was 5785 lbs. I My max was 7500. I put air bags on the front and rear. I carried 20 lbs i the front and 65 in the back. This added more weight to the front and I was able to drive with one hand. Also have you had your motorhome weighed with it as you would travel.

I apologize for not telling my chassis.It is a p30/32 chassis,92 model.I had all kinds of things done to the front but not much to the rear.I had all steering components checked for tolerance,greased all points,new air bags in the coil springs installed,tie rods,supersteer bell crank on driver side,checked gear box,changed steering pump.I had three alighnments each time adding more caster using supersteer bellcrank specs.I made sure the coach set level from front to rear with no sagging.replaced cracked bushings in the front sway bar,Rear ones are fine per tech.It has helped a little with the wander and a lot with the sway.I am gitting ready to get a second opinion on the steering component tolerance along with the gear box before I go the track bar route.the track bar is the only thing I haven't tried and that only because the tech that checked it out and did all the work said he didn't think it needed one but I think the rear extends far enough out it could be causing my problem.

joe0508 wrote:
Maybe this is not my issue because it doesn't seem as bad as the responses I'm getting.I don't pull a trailor this is a motorhome.I'm not sure if the feeling you get is similar but it does wander but not as bad as the posted are lmplying.

I was reading all the prior posts and wondering if they knew you had a Class A in your sig or not. ;)

For you it is when there is enough weight behind your rear axels causing your front tires to unload. This is a design flaw and can occur with tank placement or with the amount of coach overhang. Large class C's seem to be prone to this problem since they are built on van chassis.

You may feel it in your class A if you put as much weight as you can behind the rear axles and then get passed by an 18 wheeler. You'll feel the nose of the rig going back and forth slightly. If you tow a car it will help in keeping the rig going straight.

Hope that helps.