Wandering Nightmare

[karldavidson]

I just bought a Four Winds Citation 2006 with 12,000 miles on it. My first venture was a nightmare because it was virtually impossible to keep the RV on the road.

I have added the Safe-T-Plus and stabilizer bars on the rear, but neither has helped to a great degree. Had the alignment checked and it is okay.

My question is: Could it be that the Four Winds Citation - 26BE's wheelbase length is the culprit?

Example: The wheelbase on my rig is 171" and the total length is 27'4". The wheelbase of a shorter rig... the 24BB is 197" with a length of 26'5".

It appears that the steering problem is due to too much weight and length past the rear axle. This makes the front end too light, and therefore it wanders all over the road. Help Please... Any suggestion would be greatly appreciated.

[Harvard]

j-d wrote:
You absolutely don't want toe-OUT. What were/are your CASTER settings?

I sent a PM to crh3002 and this is his unedited response:

"actual 2.0 before 3.8 range 1.0 6.8 left front actual 2.7 before 2.7 range 1.4 7.2 right front actual 0.2 before 1,3 range -0.8 0.8 cross camber"

As best I can figure:

Left Front went from +3.8 to +2.0 Range 1.0 to 6.8
Right Front went from +2.7 to +2.7 Range 1.4 to 7.2

I do not know what the rest means other it has something to do with cross camber, defies my logic, doesn't it! :h :h :h

[j-d]

You absolutely don't want toe-OUT. What were/are your CASTER settings?

[crh3002]

I just bought my 28A in March. When bringing it home I thought that it wandered a bit more than I felt it should. Took it on a trip to Luray, probably close to 350 miles round trip, all good roads.
Steering was horrible, the line in the road would cause it to wander.
I have been a tractor trailer mechanic all my life, this is an alignment problem. I know the Ford steering is a little more touchy and apt to wandering a little. After all look at all the overhang past the rear axle.
Today I had the front end aligned at a truck spring shop that I deal with...Its not the same motorhome. Oh yeah the motorhome only has 4000 miles on it. My problem was most definitely alignment.
Camber left before 1.6 after 0.4
Right was okay
toe was out slightly brought back to 0

[Dusty_R]

Harvard wrote:

Dusty R wrote:
We bought our mh new with an E-35 under it. It's never been a problem. The only thing I've had done is have the front aligned.

Dusty

Do you happen to have an alignment report you could share? Specifically Toe, Camber and Caster settings.

Thanks.

No, that was several years ago. the front tires were not wearing even, went to Wing Foot, a truck tire and alignment place. The job they did was not right, it then pulled one way. So I gave up on them and went to a Ford Truck dealer. They fixed it right, Should have went there first place.

Dusty

[Harvard]

Dusty R wrote:
We bought our mh new with an E-35 under it. It's never been a problem. The only thing I've had done is have the front aligned.

Dusty

Do you happen to have an alignment report you could share? Specifically Toe, Camber and Caster settings.

Thanks.

[Harvard]

Chopperbob wrote:
The 5 degrees of caster really made a
Big difference for me. I already had all the other stuff
Bilstiens, air bags, swaybars, supersprings.
2001 E450 Tioga 26F. The advocates of
front end alignment I think are correct.
Drives like a suv.

Frankly, this experience raises a question. Would this RV have handled as well had only the +5 Caster been applied without the add ons? Again, I can only answer from my experience and in my case the RV already had rear air bags. I never had the experience of driving without rear air bags. So, do I think it would handle as well with just the +5 caster and NO AIR BAGS? I do not honestly think so!

In my metaphor about "input capacitors" and "feedback capacitors" I failed to state, for the best in stability, you apply both techniques to the same circuit, never one without the other.

So, the question becomes, does the OEM equipped vehicle provide enough support when used in conjunction with +5 degrees of caster?

[ron_dittmer]

JJCruiser wrote:
Both brackets are now installed but I hit a roadblock when I started to install the bar itself. It requires a couple of 1 1/8 inch wrenches to install. I don't have anything that large. I will need to pick up an open end wrench and a socket for the torque wrench. It appears the bar is going to line up well with the brackets and with good clearance between the differential and the gas tank.

Great! Keep us informed with your continued progress. Once you have successfully finished, you'll be promoted to the resident expert. 🙂

[JJCruiser]

I often think, what would we do without this users group which provides almost instantaneous information and ideas on how to live with the Ford E350/E450.

I fully agree, this forum has been very helpful to me. I made some progress this weekend on adding the rear trac bar to my E350. Both brackets are now installed but I hit a roadblock when I started to install the bar itself. It requires a couple of 1 1/8 inch wrenches to install. I don't have anything that large. I will need to pick up an open end wrench and a socket for the torque wrench. It appears the bar is going to line up well with the brackets and with good clearance between the differential and the gas tank. The pictures on ron.dittmer's website have been very helpful, I have referred to them multiple times.

Any further progress will need to wait till next weekend. I should be able to tighten the trac bar and then start the rear sway bar installation. I am looking forward to being able to test drive the rig with these improvements.

[Harvard]

QUOTE: "remember that "output" becomes "input" on a Ford chassis."

"input = output +/- process upsets", which, I believe, is true of all closed loop systems. We are both talking about the same phenomenon but I admit I need the services of a control systems engineer to step in and properly tie us together. 🙂

[j-d]

I'm not going to try and follow the electrical engineering route, but remember that "output" becomes "input" on a Ford chassis. If the coach has "body roll" the rolling causes the Swing Axle (Twin-I-Beam) to receive a steering input. The more we can limit roll (sway if you prefer), the less unwanted steering input we get. It seems improbable but the rear spring mountings (shackles and rubber bushings) allow the chassis to wander away from being centered on the axle. Since the steering is solidly mounted to the chassis in front, it doesn't wander in the same way as the rear. Rear wandering causes the coach to try to stray out of its lane. Driver corrects, and staying in lane becomes a seesaw battle. Rear Track Bar (Panhard Rod) fights that by keeping the Axle centered under the Chassis.

[Harvard]

JJCruiser wrote:

Its like an amplifier circuit where a capacitor across the input prevents noise from entering the amp while a capacitor in the negative feedback loop serves to correct the problems that get by the input. JMO

As an electrical engineer, I appreciate how you worded this. I don't know for sure yet, but I am anticipating that I will need more then just the input capacitors.

Keep in mind that you already have some "feedback capacitance" in that you have at least +2.5 to +3.5 Degrees of Caster (assumed to be worst case) so adding more input prevention could do the trick. This appears to be the case in the experience of rcase13 earlier in this thread. On the other hand we have a recent thread where DunnInn seemed to apply everything we have in our arsenal and still did not obtain satisfactory results.

Each of these RVs are dynamically unique and we can only hope to protect our investment and tame those combinations which are unacceptable to drive. The only reason I am so vocal about the +caster is because of my personal experience which is limited to one particular E450 with air bags. I wish we had more alignment reports and feed back like Glenn Lawton provided so we could develop a wider picture of the real world.

I often think, what would we do without this users group which provides almost instantaneous information and ideas on how to live with the Ford E350/E450.

[ron_dittmer]

JJCruiser wrote:

j-d is correct. It's all a short coming with Ford. Ford really needs to equip every "Marketed For Motor Home" chassis with the parts we add afterward.

I feel that should be mandated by the NTSB because it really is a matter of safety with a very easy and affordable solution that won't hurt Ford one bit. They only need to install parts already available, and pass the residual cost into the purchase price.

I am not an advocate for "Government Regulations", but this is one area they need to get involved to address this safety issue. The answer is easy and the cost is negligible to all parties. Ford is already installing those parts.....just install the right parts.

I agree. I know when I bought my RV, I did not expect I would be crawling around underneath adding parts to the suspension. I have a 2007 E350, did Ford make any suspension improvements to the current model? I do like all the power that I get out of the V10.

In 2008, Ford started installing a rear stabilizer bar on the E350. But it along with the front bar are both wimpy on both the E350 & E450. So the 2008-2013 are definitely better, but not as good as yours is now in the way of stability.

[Dusty_R]

We bought our mh new with an E-35 under it. It's never been a problem. The only thing I've had done is have the front aligned.

Dusty

[JJCruiser]

j-d is correct. It's all a short coming with Ford. Ford really needs to equip every "Marketed For Motor Home" chassis with the parts we add afterward.

I feel that should be mandated by the NTSB because it really is a matter of safety with a very easy and affordable solution that won't hurt Ford one bit. They only need to install parts already available, and pass the residual cost into the purchase price.

I am not an advocate for "Government Regulations", but this is one area they need to get involved to address this safety issue. The answer is easy and the cost is negligible to all parties. Ford is already installing those parts.....just install the right parts.

I agree. I know when I bought my RV, I did not expect I would be crawling around underneath adding parts to the suspension. I have a 2007 E350, did Ford make any suspension improvements to the current model? I do like all the power that I get out of the V10.

[JJCruiser]

Its like an amplifier circuit where a capacitator across the input prevents noise from entering the amp while a capacitator in the negative feedback loop serves to correct the problems that get by the input. JMO

As an electrical engineer, I appreciate how you worded this. I don't know for sure yet, but I am anticipating that I will need more then just the input capacitors.