E350/E450 Handling Problems are caused by too little + CASTER

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OP here, for the record.

I now have driven 40,000 miles on this 2004 E450 since late 2010, and early 2011 when I started this thread. I can assure you I have not experience any abnormal tire wear.

Just to recap how my DIY job unfolded.

1: Took it in for an alignment and all they did was tweak the toe and never touched the caster or camber.
2. In an RV park, I adjusted my existing Ingall concentrics for +2.0 more caster each side and set the Ingalls for 0.0 camber on each side.
3. Again in the RV Park, I tweaked the toe using a tape measure.

And now being 40,000 mile later I know it worked out good.  Cheers
 
Arfdog said:
Thanks very much for the pics.  I had the Ingalls 594's installed with the LH caster coming out at 5.4 and the RH coming out at 5.9 and the bushings did not have to be maxed out.  My vehicle is a 2012 Itasca Impulse on a Ford E450 chassis.  Guess this shows you can't simply set the bushings at MG and MS as the base axle casters can vary.

I did do a short test drive and it looks like the handling has been considerably improved.

Thanks Again,

Jim
Click to expand...

I think you can simply set the bushings at MG and MS and you would have more then +5 degrees caster, more is better. My unit sits about 1 degree nose down (I have rear air bags), if it were leveled I would have about +6 and +6.5 degrees of caster. I know the final camber does not matter one iota because it changes as soon as you sit a driver and a passenger in the front seat. JMO.
 
OP Here. Just bumping this to the surface because there are still a steady stream of wandering RVs.
 
99dart said:
Thinking about taking our new to us 2016 Quantum WS31 in for an alignment. Should I assume that I will need the new bushings and go ahead and buy them beforehand?
Click to expand...

I took my RV to Josam in orlando.  I've been told they are alignment experts and I couldn't find a local shop that was convenient and able to do the RV.
Actually it has been a while so I should probably plan a trip back....

Anyway, I had known about Harvard's advice at the time and was asking them for more caster.  what they told me was that the caster adjustment is a trade-off with camber.... to get more caster positive, it throws off the camber, they said to the point of causing problems with bump-steer....
Anyway, they put it where they suggest was the best compromise.  Not nearly as high as Harvard suggests, but it performs well enough.

I have no idea how these bushings would affect camber.  harvard, maybe you can chime in on that?  Anyway, I'd say that if you want to follow the advice I'd go to the alignment shop with the bushings in hand....
something I have in the back of my mind that I might do some day... but honestly with the tire pressures set by weight and the alignment as was done by Josam, it's good....no luxury car, but it's good.
Still, I wonder...should I pick up some bushings and head back in for re-alignment?...hmmm, something to consider....
 
99dart said:
Thinking about taking our new to us 2016 Quantum WS31 in for an alignment. Should I assume that I will need the new bushings and go ahead and buy them beforehand?
Click to expand...

Assuming you have a E450 chassis, if the alignment shop is knowledgeable they will have the sleeves in stock or know where to source them on the spot. IMO.
 
blw2 said:
I took my RV to Josam in orlando.  I've been told they are alignment experts and I couldn't find a local shop that was convenient and able to do the RV.
Actually it has been a while so I should probably plan a trip back....

Anyway, I had known about Harvard's advice at the time and was asking them for more caster.  what they told me was that the caster adjustment is a trade-off with camber.... to get more caster positive, it throws off the camber, they said to the point of causing problems with bump-steer....
Anyway, they put it where they suggest was the best compromise.  Not nearly as high as Harvard suggests, but it performs well enough.

I have no idea how these bushings would affect camber.  harvard, maybe you can chime in on that?  Anyway, I'd say that if you want to follow the advice I'd go to the alignment shop with the bushings in hand....
something I have in the back of my mind that I might do some day... but honestly with the tire pressures set by weight and the alignment as was done by Josam, it's good....no luxury car, but it's good.
Still, I wonder...should I pick up some bushings and head back in for re-alignment?...hmmm, something to consider....
Click to expand...

"Bump Steer" in the context of camber is BS, an excuse not to learn something new.... Also, if you reread my posts all I did was add +2.0 degrees of caster and 0.0 degrees of camber. The resulting camber setting has been close enough "for all practical purposes". That is what I did 40,000 miles ago along with a DIY Toe adjustment and I have never had any tire wear issues.

Bump Steer has probably been part of front end dynamics ever since caster was invented. IMO. It is an effect that is not an issue where caster settings are set to "practical settings". Again, IMO.

Most alignment shops are so used to the profits realized from their "tweak the toe and you are good to go" approach to the Ford Trucks and they do not want to change. IMO



 
Harvard said:
Assuming you have a E450 chassis, if the alignment shop is knowledgeable they will have the sleeves in stock or know where to source them on the spot. IMO.
Click to expand...

Thanks for the quick response guys! I will have to call a couple places to find out if they can do a MH alignment. I'm in a small town, so we shall see.
 
99dart said:
Thanks for the quick response guys! I will have to call a couple places to find out if they can do a MH alignment. I'm in a small town, so we shall see.
Click to expand...

Here is a link to a very recent testimonial by a handle named "2kGeorgieBoy". I suggest you print it off and take it with you.

http://www.rvforum.net/SMF_forum/index.php/topic,112427.30.html

START QUOTE
Jeff..Although we have a 2000 Georgie Boy 31' Maverick "C" on  a Ford E450 chassis, I can fully agree on the caster effects, at least for us.  When we got the unit in  Jan 2014, the dealer had us take into a  truck shop for an alignment. It turned out OK....A trip to Moab shortly there after brought out the problems. I then started reading the threads and comments here about the caster settings....esp., from Harvard. I checked the data from the first alignment and found that it was set at about 3 1/2 degrees positive...about in the middle of Ford's recommended range. Shortly before a cross country trip to Maryland in fall of 2016, I returned to the shop where the first alignment was done. I talked to the service manager and he knew of the problems with the E450's and was happy to increase the caster as I asked. The alignment tech was also familiar with it and ended up with settings close to 5.5 degrees positive. WHAT A DIFFERENCE! The unit tracked straight down the road, passing semis no longer caused a white knuckle hold on the wheel, and overall it was just a lot more enjoyable. It did however increase steering effort a little but not anything to worry about.  But,be sure that the shop you go to is willing to "think outside of the box". Our first alignment was "plain vanilla", right in the middle like it was always done. Second time out, they were very willing to increase settings beyond what normally would be done, and still stay with in Ford's guidelines (0-7 degrees, I believe). I realize that our E450 chassis is an entirely different animal than yours, but I was trying to add support to the caster increase thinking and how it helped us......if you go down that road.
END QUOTE
 
Thanks, Harvard and others on this thread  for the education to  refine  my plan to improve  the suspension on the E-450 chassis of my 2018 Leprechaun 260DSF. as follows:
1. Sumo springs on the front. Back came with firestone air bags
2. Roadmaster steering stabilizer
3. Roadmaster rear anti sway bar in rear
4. Koni adjustable shocks.
After Installation  I will have the front wheels realigned, watching caster, after ensuring the rig is level front to back by proper inflation in the rear airbags.
The air bag instructions tell me that air bag inflation is set to have a level a loaded coach from back to front  and side to side.  Now understanding caster physics , I see it can be effected by coach level back to front .
Now back  to airbags.  Firestone manual says, " Normal pressure loss should not exceed 3 ? 4 psi per week when the air springs are inflated to 50 psi and should be checked monthly.
Since I'm adding a tire pressure monitoring system (TPMS), I'll add caps for the air bags. 
Gratefully
Richard
 
Tire Inflation vs Caster

This is just a theory:

When the pressure in a tyre is reduced the contact patch is enlarged. The total dynamics of the rolling tyre start where the ?rubber hits the road?. As such one half of the increase in the contact patch length is added to the mechanical trail there by increasing the straight line stability in the same manner as increasing the caster angle.

(Mechanical Trail is the moment arm between the steering pivot point (fore) and the center of the contact patch (aft))
 
Handyman said:
Hello,

Reading this thread, makes it all clear to me.....

We made last year in June and this year in Mai a tour of about 3500 and 3840 miles, with rental motorhomes, a 26 type C from Road Bear and a C25, factorynew one from Cruise America. Last trip was from Chicago to SF. Both were C350 Ford's.

And since we, as Europeans, are used to the stability of our own MH, a Fiat with AL-KO chassis, I was astonished about the very bad handling ... And even more this year, since we passed the north of Texas, during those bad weather period. I was realy steering all the time. Checked even, several times if there wasn't any visible problem with the tyres, airpressure or axle .... Pfffff .... Even thought a brief moment perhaps there must be bolts, not thightend enough .... Heavy winds made driving almost a terrifying experience!

But we still enjoyed our trip and stay in your wonderfull, beautifull country!
Thanks also for the hospitality and friendliness people showed us.

Bye, Dani?l
Click to expand...

Just for something to do I googled "Mercedes Sprinter Alignment Specifications".

The LH Caster Setting is +5.8 Degrees and the RH Caster Setting is +6.3 Degrees.

That pretty much tells the story of Europe and Ford accepted standards when it comes to +Caster.
 
Harvard said:
Our 2004 E450 28 Foot handled terrible until we added additional + Caster to the front wheels.

The Ford Spec for front end CASTER is:

LH +1.3 to +6.8 Degrees
RH +1.8 to +7.3 Degrees

Our unit was:
LH +3.3 Degrees
RH +3.5 Degrees

We added + 2.0 degrees, so we are now at:
LH +5.3 Degrees
RH +5.5 Degrees.

Alignment problems on the E series follow the 80/20 rule in the sense that TOE and CAMBER is 20% of the story while CASTER is 80% of the story. TOO LITTLE CASTER will amplify any external force many fold to the detriment of stability.

If your unit feels like the steering box needs to be tightened up it is because of TOO LITTLE + CASTER.
If cross winds and wind gusts cause havoc it is because of TOO LITTLE + CASTER.
If you think the tail is wagging the dog it is because of TOO LITTLE + CASTER.
If you are needing to drive it all day and never relax it is because of TOO LITTLE + CASTER.

If your unit drives GREAT, like an SUV, it is because you have a proper amout of + CASTER which I am guestimating to be about +5.0 degrees or more.  (Note: The RH caster is always more then LH (CROSS CASTER = LH - RH))
Click to expand...
 
I know this is a old thread and I'm a new member but when I recently bought my 2017 Thor Freedom Elite class C, I had a white knuckle ride home from where I bought it in Arizona back to California. The drive was very disappointing, when I returned home I sent Ford a letter about my experience and they actually called me. I was informed that Ford gives each new RV chassis a generic alignment as it rolls off the assembly and stated the RV manufacturer who adds the coach to the chassis should give each unit an alignment, even he admitted that it is rarely done. He suggested that I contact "Thor" of course Thor informed me that they do not do alignments on their new coaches and it is not covered under the purchase of the coach. So if you buy a new coach make sure you get a wheel alignment, it runs a couple hundred dollars. That, and a couple of suspension upgrades eliminated the problem. Hope this helps.
 
Any alignment shops in Albuquerque NM that are aware of this issue and know how to correct it?
2009 Ford E450 Class C Lazy Daze. Recent ball joints change corrected vibration however alignment done to septics and told problem is with tow car not alignment.
 
Hello!  I'm new to the forum. Just bought a new Minnie Winnie 25B on the 450 chassis.  I've put about 400 miles on it so far,  mostly with a trailer in tow.  It's been somewhat demanding to drive.  Just got the alignment done in OKC, and drove the 20 miles home.  The increased caster made this a whole new machine.  Less sensitivity to the wind,  far fewer necessary steering corrections.  I was driving 75 down the interstate one-handed. 

Thanks for all the info!
 
Approaching the 8th anniversary of this thread, the way I see it:

The Ford assembly line installs fixed non adjustable caster/camber sleeves that are identical on every chassis.

So, as near as I can figure, IF the RV builder does nothing about replacing the caster/camber sleeves then:

If the final RV build is 1 degree nose down the runtime caster is going to be about +3.5 degrees.
If the final RV build is nose level the runtime caster is going to be about +4.5 degrees.
If the final RV build is 1 degree nose up the runtime caster is going to be about +5.5 degrees.

Thus, some have a problem, some do not....???
 
Hi Harvard,

Thanks for your post and generous follow-up for the past many years. I have 32 feet class C Forrest River SunSeeker 2018 built on a 2017 Ford E-450. After only 25K miles on it (bought it new), I wore out my front wheels that came with the RV (Hankook). I thought this is low mileage to do such damage. (see attached. The driver's side attached was worse than the passenger and both had worn further from the inside than the outside).

I replaced the 2 front tires with Cooper tires. I followed up by doing the alignment at the same shop. Unfortunately, once I left, the RV started to pull left, unlike any time I had it for the past three years. When I went back to the shop, they drove it and did the alignment again. The same thing happened immediately, so they did it one more time.

While trying to find a cause for this strange pull, I stumbled upon your online postings on the topic. I emailed them to the shop and we agreed to order the sleeve (Not sure which brand name yet).

My question is:
You mentioned the following in different spots:
"If you find that your RV CASTER is ALREADY above +5.0 then DO NOT ORDER ANY PARTS, they will not help you beyond where you are now sitting."

"The Ford assembly line installs fixed nonadjustable caster/camber sleeves that are identical on every chassis. So, as near as I can figure, IF the RV builder does nothing about replacing the caster/camber sleeves then:

If the final RV build is 1 degree nose down the runtime caster is going to be about +3.5 degrees.
If the final RV build is nose level the runtime caster is going to be about +4.5 degrees.
If the final RV build is 1 degree nose up the runtime caster is going to be about +5.5 degrees."

--------------

Q: See attached the spec for my E450 and my before specs (attached) and another photo while they were working on it. These numbers seem to be very high close to your recommended specs.
LH +5.3 Degrees
RH +5.5 Degrees.
Maybe due to the factory's nose built for my RV as you mentioned?? I am not sure!

So do you recommend replacing the current sleeve (photo attached) or only keep them and do the spec as you recommended? Thank you!

PS. I trust the shop very much. Great guys. My guess, they just weren't familiar with the needed spec you suggested. You've been through this for many years now and your feedback will be valuable for us. If not on time, then I'll update anyway. Thanks again!

01. Tire.JPG02. Spec.JPG03. Spec before.JPG05. Spec after.JPG04. sleeve.JPG
 
SoloRover: The tire wear shown is very excessive and there is no indication of a cause for that wear in the front end before alignment numbers. So, it may be the problem is with the rear axel being out of alignment. If the rear axel alignment is dog tracking it should be apparent in the rear view mirror while driving down a road that has line marking. IMO.
 
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