Crazy steering wobble/shake

I just experience the same thing with the family car. It has very low miles with seven year old tires. A steel belt in the tire broke and I thought the front end of the car was going to fall off. Driving at walking speed, the front of the car would move side to side. At higher speeds it felt as though the tires had never been balanced. New tires were put on and all is well. Best of luck, David

I have had to deal with Death Wobble many times with Jeeps. It's always been something worn or bent in the front suspension or steering. Some event sets it going, usually a pot hole in the road, out of balance tires, or the alignment is way out. Once the oscillation starts it will usually continue until you stop as the forward motion is what is powering it.
Since this issue is on a DP I would suspect the front track bar bushings first but it could be anything.

Dave,

The new toad is likely a contributor -- as I just had it set up with the Blue Ox and this was my first time towing it. it's a new 2013 VW Passat - so i don't think the car is worn out, but i'll check the towbar angle and the rear view camera.

A few years ago I repeatedly experienced the same symptoms as you while while towing a small car with my class A gas rig. I thought my front wheels were about to fall off! I had the front end of my class A MH checked and found some worn components that were replaced. This fixed the problem for a while.
I traded the MH for a new DP, then about 6 months later, I began having the same problem. Fortunately the new MH had a rear-view camera and I could see the shaking was coming from the towed car. It turned out that the front struts on the car were worn out and were unable to quickly stop the roll oscillation that was created when finishing a turn. It was caused by some interaction between the car body rolling in the turn, small normal steering changes that happen when all cars experience body roll, and the normal lateral play in the hitch and tow bar.
After having the car's front struts replaced there has been no repeat of the problem for about 2 years. Before I had the car's front struts replaced, I was able to prevent the shaking by allowing the turn to complete and the car to straighten out before accelerating, but like your situation once the shaking started I had to come to nearly a complete stop to make the shaking abate.
While troubleshooting I would not overlook defects in the car, the attachment and integrity of your adapter plate, tow bar, and the hitch on your MH.
If you find no problem with the above items and you can verify using your rear-view camera that the problem is with the car, You might check the angle of the tow bar to the ground when towing and on level ground. Depending on the model of Blu Ox tow bar you have, I believe they recommend that the bar sits level or slightly raised in the front.(at the MH receiver) check your tow bar manual to be sure. If the angle is off quite a bit,it seams to me that body roll could be induced in addition to the normal roll caused by centrifugal force created in the turn, This additional body roll might be enough to start the chain of events that cause the shaking.

Dave

The only things that have substantially changed in the coach in the last few weeks was the new governor in the air pump and the new VW Passat TOAD and Blue Ox towbar.

Weights and things like that have been pretty consistent. The coach weighs about 25,000lbs with my stuff in it. Towing a TOAD adds no weight to the coach, other than the drag of the coach - no tongue weight.

As for Tongue weight, I have recently towed a trailer with over 1000lbs of tongue weight that would significantly unload the front axle, but I typically use weight distribution bars. No issues while towing.

Well Gang,
In the OPs answer to me on the history of his ownership of the coach, he stated he's had it for quite a while, many, many miles and it: HAS NEVER DONE THIS BEFORE! So, I suspect that, he's driven with just about every combination of loaded tanks, unloaded tanks, loaded coach, unloaded coach, acceleration, deceleration, cornering, bumps, dips, hard stops, soft stops, towing, not towing, and much, much more and any combination thereof.

And, It's never done it before. So, is it possible that, for the very first time, after years of ownership, that, he's encountered a driving/coach condition that he's NEVER encountered before? I kind-a doubt it. I am not a front end expert, nor a physics professor so, trying to figure out what kind of weight transfer/shift that could cause his situation FOR THE VERY FIRST TIME, after owning the rig for that long, would be very tough.

Our rig, the sister ship to his, an 04 Itasca Horizon 36GD with the 330 CAT, (only ours is 3' shorter) is an incredibly heavy rig. I could load those black, gray, fuel, and, 31 gallon propane tanks in any combination of full/empty and (and have had it at multiple levels of each) and never tell the difference in handling or, performance.

This is why I asked him how long he's owned it, and, has it EVER DONE THIS BEFORE. His answer was, a long time and, it's never done it before. So, what's changed in the last couple of weeks that might be the issue here? He's had supposed reputable companies analyze the front end, alignment and more. An unbalanced tire, enough to cause shaking, is going to manifest itself each and every time one reaches the speed at which it starts to cause issues. But, this problem is not consecutive. It happens, then, it doesn't happen with driving conditions duplicated. I hate when some things "malfunctioning" only part of the time.
Scott

But original post said it was smooth until he come to a stop and made a left turn. What does that have to do with the load shifting all of a sudden? Does not make sense to me. Now if it had been doing it from the start THEN there might be something to that, but it is hard to beleive that it could be the load distribution after making a left turn.

wolfe10 wrote:

Jim@HiTek wrote:
Imbalance from left to right? Like if one side of your RV is overloaded and the other side light?

Did this happen with the holding tanks empty? Or full?

I've only had the death wobble twice, both times it was with nearly full holding tanks, grey, black and water. Both times, slowing to a stop caused it to go away. Both times the front end components checked out OK. Now I always dump before driving.

Jim,

Suspect all your tanks are in back. When full, they UNLOAD the front axle, making it much more sensitive to any "out of spec" conditions.

I agree with Wolfe10. When you accelerate, you are "unloading" the front axle. I would re-weigh the coach and move as much weight to the front as possible. That would be a very cheap fix if it works.

Since we are shooting in the dark, with higher air pressure you might have an "S" cam sticking after you release the foot brake. ????

Jim@HiTek wrote:
Imbalance from left to right? Like if one side of your RV is overloaded and the other side light?

Did this happen with the holding tanks empty? Or full?

I've only had the death wobble twice, both times it was with nearly full holding tanks, grey, black and water. Both times, slowing to a stop caused it to go away. Both times the front end components checked out OK. Now I always dump before driving.

Jim,

Suspect all your tanks are in back. When full, they UNLOAD the front axle, making it much more sensitive to any "out of spec" conditions.