Sway Control
- Thread starter Working Retired
- Start date
Hi WR -
We have been looking into how to best reduce the rock and roll, and "Almaden RV" (in San Jose) suggested this very same 1209-131 for our 2014 Sprinter based Itasca 26 G. Are you still happy with this or have you had second thoughts? 2 different Camping Worlds suggested just replacing the rear anti-sway with a stronger one....and a friend on the East Coast swears using Timbren bumpers made the biggest difference.....but i have also been told this would give a lot more road vibration since there is always contact between the vehicle and the axle. Any input is most appreciated! Thank you in advance!
We have been looking into how to best reduce the rock and roll, and "Almaden RV" (in San Jose) suggested this very same 1209-131 for our 2014 Sprinter based Itasca 26 G. Are you still happy with this or have you had second thoughts? 2 different Camping Worlds suggested just replacing the rear anti-sway with a stronger one....and a friend on the East Coast swears using Timbren bumpers made the biggest difference.....but i have also been told this would give a lot more road vibration since there is always contact between the vehicle and the axle. Any input is most appreciated! Thank you in advance!
Hi TD -
Did you get the 1201-131 installed? The sway on our 2015 Itasca is outrageous! Having considered Timbren and Sumo bumpers (said to work but increase vibration because of constant contact between cabin and axle), replacing the rear sway bar (the only option offered by Camping World), and ruling out air bags this seems the best first step, followed by the Koni if necessary.....We would love to hear how you feel about your upgrade!
Did you get the 1201-131 installed? The sway on our 2015 Itasca is outrageous! Having considered Timbren and Sumo bumpers (said to work but increase vibration because of constant contact between cabin and axle), replacing the rear sway bar (the only option offered by Camping World), and ruling out air bags this seems the best first step, followed by the Koni if necessary.....We would love to hear how you feel about your upgrade!
Suspension consists of springs, dampers (shocks) and sway bar. Each one has a specific function in suspension design. Sway bars keeps the chassis from leaning when for example a truck passes, or going around a corner at higher speed. Sway bars do absolutely nothing good for rocking! Folks just buy them because they are one of the cheapest mods that can be made to the suspension.
As far as I can tell, all Sprinter based motor homes with a high center of gravity that are maxed out on weigh, have a rocking problem. The solution is two fold. You need more damping in the shocks as well as more springs. Get Knoi reds, adjusted to max damping for both struts and shocks. Other shocks on the market do not work nearly as well as the Konis. As far as springs, I recommend Super Springs Helper Springs.
http://www.sdtrucksprings.com/super-springs/dodge/sprinter-3500
As far as I can tell, all Sprinter based motor homes with a high center of gravity that are maxed out on weigh, have a rocking problem. The solution is two fold. You need more damping in the shocks as well as more springs. Get Knoi reds, adjusted to max damping for both struts and shocks. Other shocks on the market do not work nearly as well as the Konis. As far as springs, I recommend Super Springs Helper Springs.
http://www.sdtrucksprings.com/super-springs/dodge/sprinter-3500
sailquik
Well-known member
Couple of points here:
As calbiker suggests, anti-sway bars is a bit of a misnomer.....they are more properly termed "anti-roll bars" as their main function is to keep all of the vehicle above the
axles (where the anti-roll bars are mounted/attached) from rolling when there are forces that tend to cause it to roll about it's longitudinal axis.
The forces:
Going into any sort of corner, the body will tend to roll on the longitudinal axis towards the outside of the corner.
Cross winds will tend to push on the upwind side of the body and cause it to roll on it's longitudinal axis.
The "air wakes" off trucks and larger vehicles will tend to create wind forces that will cause the body to roll.
The complete function of the "anti-roll" bar is to limit the amount the body can roll by transferring some of the upward force on the side toward which the body is rolling
across (through the stiff anti-roll bar) to the unloaded side as a downward force.
They do very little for sway as for every action (upward force on the loaded end of the bar) there is an equal and opposite downward force on the unloaded end of the bar.
So anti-roll bars can often increase the back and forth sway of a Sprinter rear suspension as the up and down forces on the ends of the anti-roll bar are reduced in a number of cycles.
It's the function of the springs and shock absorbers to limit the number of oscillations that pass back and forth thru the anti-roll bar.
Sumo springs/Super Springs/Timbren rubber springs and SES setups are all things that can reduce the back and forth sway of a Sprinter as they operate to support
each side of the body independently from the other side so they tend to damp out the anti-roll bar induced oscillations.
Also, properly installed Timbren SES or front rubber springs are not designed to be in constant contact with the axle when the vehicle is at normal loading weight.
There is supposed to be an air gap or space between the end of the Timbren and the perch/plate on the axle so the Timbren springs only contact the axle when
fully loaded or when the body rolls far enough for them to engage.
Hope this helps,
Roger
As calbiker suggests, anti-sway bars is a bit of a misnomer.....they are more properly termed "anti-roll bars" as their main function is to keep all of the vehicle above the
axles (where the anti-roll bars are mounted/attached) from rolling when there are forces that tend to cause it to roll about it's longitudinal axis.
The forces:
Going into any sort of corner, the body will tend to roll on the longitudinal axis towards the outside of the corner.
Cross winds will tend to push on the upwind side of the body and cause it to roll on it's longitudinal axis.
The "air wakes" off trucks and larger vehicles will tend to create wind forces that will cause the body to roll.
The complete function of the "anti-roll" bar is to limit the amount the body can roll by transferring some of the upward force on the side toward which the body is rolling
across (through the stiff anti-roll bar) to the unloaded side as a downward force.
They do very little for sway as for every action (upward force on the loaded end of the bar) there is an equal and opposite downward force on the unloaded end of the bar.
So anti-roll bars can often increase the back and forth sway of a Sprinter rear suspension as the up and down forces on the ends of the anti-roll bar are reduced in a number of cycles.
It's the function of the springs and shock absorbers to limit the number of oscillations that pass back and forth thru the anti-roll bar.
Sumo springs/Super Springs/Timbren rubber springs and SES setups are all things that can reduce the back and forth sway of a Sprinter as they operate to support
each side of the body independently from the other side so they tend to damp out the anti-roll bar induced oscillations.
Also, properly installed Timbren SES or front rubber springs are not designed to be in constant contact with the axle when the vehicle is at normal loading weight.
There is supposed to be an air gap or space between the end of the Timbren and the perch/plate on the axle so the Timbren springs only contact the axle when
fully loaded or when the body rolls far enough for them to engage.
Hope this helps,
Roger
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Hi Roger -
THANK YOU for taking the time to put your views in....we had decided to add the extra anti-sway bar first because of the reported road noise/rough ride that Timbren shocks (etc) cause. It seems our unit is constantly on "maximum load' so I wonder if there would be a way to have this space between the axle and body on our vehicle? We haven't ordered the
Roadmaster Anti-Sway Bar | Rear Aux sway bar 1 1/2 diameter retains factory bar.
[ 1209-131 ]
http://www.hitchsource.com/roadmast...-12-diameter-retains-factory-bar-p-36347.html
yet, and do see the wisdom of simply limiting how far the springs can compress over each axle if we can avoid the rough/loud ride issue.....sigh!
It shouldn't be this difficult to get a decent ride on a brand new Itasca motor home!
Wouldn't the extra anti-roll/sway support limit how far the coach would roll, with stiffer damping so there was less back and forth? The one thing i do know is we are very green with anything mechanical and hope to make the 1 right move for us based on what the experts (that would include YOU) suggest. Any other gems you would care to offer?
Thank you again (and again) for your time Roger!
THANK YOU for taking the time to put your views in....we had decided to add the extra anti-sway bar first because of the reported road noise/rough ride that Timbren shocks (etc) cause. It seems our unit is constantly on "maximum load' so I wonder if there would be a way to have this space between the axle and body on our vehicle? We haven't ordered the
Roadmaster Anti-Sway Bar | Rear Aux sway bar 1 1/2 diameter retains factory bar.
[ 1209-131 ]
http://www.hitchsource.com/roadmast...-12-diameter-retains-factory-bar-p-36347.html
yet, and do see the wisdom of simply limiting how far the springs can compress over each axle if we can avoid the rough/loud ride issue.....sigh!
It shouldn't be this difficult to get a decent ride on a brand new Itasca motor home!Wouldn't the extra anti-roll/sway support limit how far the coach would roll, with stiffer damping so there was less back and forth? The one thing i do know is we are very green with anything mechanical and hope to make the 1 right move for us based on what the experts (that would include YOU) suggest. Any other gems you would care to offer?
Thank you again (and again) for your time Roger!
Rufflesgurl
New member
Walking Retired - I have a 2016 Navion 24G and am not happy with the rough ride and sway.
You are in the Sacramento area? Where did you get your modifications done? I am closer to Tracy and would consider some type of help for a better riding, handling MH.
Haven't even put 1,000 miles on it yet, and it is at Mercedes for the second time for the amber check engine light. Something about a module that needs replacing. Pretty scary engine messages appeared on second trip.
In lieu of the above, I'm not a happy camper!!
Linda
You are in the Sacramento area? Where did you get your modifications done? I am closer to Tracy and would consider some type of help for a better riding, handling MH.
Haven't even put 1,000 miles on it yet, and it is at Mercedes for the second time for the amber check engine light. Something about a module that needs replacing. Pretty scary engine messages appeared on second trip.
In lieu of the above, I'm not a happy camper!!
Linda
Well here is my opinion. I have a 2006 Winnebago View 24H. Bought it with 20000 miles on it. I did not like the sway or ride. I installed the koni rear shocks. Have the stock front shocks. I installed the sumo springs spring bumpers in the rear. I had to replace the stock air bag option due to the previous owner never using them. They had 0 air and the bags were worn from rubbing against them selves. I have the stock sway bar. I inflate the bags to 45 psi. run the rear tires at 63psi and the fronts at 60. I have found this to give me the best ride and least sway. I am happy now. Much better control when passed by a semi. Body roll is much better. I attribute that to the air bags. Took a while to get the pressure that would work the best.
GaryJ
Here since 2006
CPH628,
I have a similar 07 View (06 chassis) and first tried the Roadmaster bar, which improved drivability but was to no avail for rocking. Then I installed Timbrens and both the amplitude and number of oscillations were reduced by about half in low speed rocking. The rear suspension is somewhat more harsh now, especially on segmented highways.
Gary
I have a similar 07 View (06 chassis) and first tried the Roadmaster bar, which improved drivability but was to no avail for rocking. Then I installed Timbrens and both the amplitude and number of oscillations were reduced by about half in low speed rocking. The rear suspension is somewhat more harsh now, especially on segmented highways.
Gary
Upgraded the stock sway bar with a roadmaster replacement and it has made a considerable difference. I have a heavy pop-top in my rig that induced noticeable sway. Upon removing the stock bar, I was appalled to see how flimsy and small in diameter it actually was. I'm sure it's engineered to be just perfect by German engineers, but in reality, it's next to useless. The ride is much stiffer and controllable now. It was a worthy upgrade.
In my experience:
-The greater the collective spring rate (metal, air bags, Sumos) the higher the resistance to roll with the sacrifice of ride quality.
-Sway bars can be too strong, being that what one wheel "experiences" transfers to the whole vehicle.
-Shocks can be so rigid that they flatten the vehicle in resistance to sway, but tend to offer very hard ride qualities.
Seeking the balance of ride quality, sway resistance and general vehicle control is not always easily attained.
Koni makes very good shocks, but it concerns me to start out with adjusting them to full hard.
We have a 2015 3500 camper. Not satisfied with its handling I almost immediately exchanged the stock shocks for Bilstein HD shocks front and rear. I then exchanged the rear stock sway bar for the Helwig unit. Being almost there, I installed the Sumo helper suspension bumpers front and rear. The camper is now much improved; I am feeling it is almost there. There is still a small bit of sway but greatly reduced and acceptable. We still feel semi trucks going by but hardly notice their aerodynamic influence. The ride quality continues to be very good (remembering that this is a 3500 series vehicle with a 10,000GVW rating)
What else would I change?
-I would send out the front shocks to Bilstein and have them re-valved for about 10% increase in compression and 20% increase of resistance in extension.
-Would find (so far not available) a thicker front sway bar.
I think I would then be very happy.
Haasman
-The greater the collective spring rate (metal, air bags, Sumos) the higher the resistance to roll with the sacrifice of ride quality.
-Sway bars can be too strong, being that what one wheel "experiences" transfers to the whole vehicle.
-Shocks can be so rigid that they flatten the vehicle in resistance to sway, but tend to offer very hard ride qualities.
Seeking the balance of ride quality, sway resistance and general vehicle control is not always easily attained.
Koni makes very good shocks, but it concerns me to start out with adjusting them to full hard.
We have a 2015 3500 camper. Not satisfied with its handling I almost immediately exchanged the stock shocks for Bilstein HD shocks front and rear. I then exchanged the rear stock sway bar for the Helwig unit. Being almost there, I installed the Sumo helper suspension bumpers front and rear. The camper is now much improved; I am feeling it is almost there. There is still a small bit of sway but greatly reduced and acceptable. We still feel semi trucks going by but hardly notice their aerodynamic influence. The ride quality continues to be very good (remembering that this is a 3500 series vehicle with a 10,000GVW rating)
What else would I change?
-I would send out the front shocks to Bilstein and have them re-valved for about 10% increase in compression and 20% increase of resistance in extension.
-Would find (so far not available) a thicker front sway bar.
I think I would then be very happy.
Haasman
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Old Crows
Calypso 2014 View Profile
Linda,
Oft misunderstood is role tire pressure plays out in the problem. The tire's sidewall is part of the shock absorbing "système".... The tire has to flex, give, bend and "work" to help absorb upward motion. More pressure is not better. Check the placard by the driver's door. Set "cold" no higher than the PSI specified on the placard.
My solution was to install Sumo "Solo" bump stop replacements from and rear. As has been reflected on and stated repeatedly, you want to dampen the amplitude and frequency of the side to side oscillations without adding energy to the "system."
Anti-roll bars, sway bars if you will, are torsion bars that transfer force to the opposite side of the coach in a "push-pull" fashion. Like a teeter totter, the coach pushes back and once coupled in frequency to the initial push the amplitude of the teetering. Like "pumping" a swing. As the forces couple the greater the rocking...
Sumo Solos are larger and especially made bump stop that work in compression and absorb the upward forces in the axle without transferring "push back" (equal and opposite reaction) to the coach & chassis. (Being on the ground the tires, springs and axle are not going to give way and any stored energy is going to transferred to the coach.).
Think of them as big, rubber baby buggy bumpers.... or pillows... That soak up all that motion and energy WITHOUT transferring it to the coach.
OK, Crows....what's it really like???? Sumos are a 98% solution. The slight downside is there is a tiny bit more noise and roughness from the rear on some road surfaces. Because the rear Sumos are in contact with the axle. When you board through the coach door, it's stable and doesn't bob around like a rowboat. It is stable when you walk around inside. Rocking when entering and leaving gas stations, parking lots and uneven surfaces, chuck holes is greatly reduced in amplitude and frequency. And this bad behavior is quickly curbed.
One in awhile it will act up.... But rarely if you pay attention to road surfaces.
Highway handling in all conditions is greatly improved....
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Cal
My Sumo's are the Solo's as Old Crows has. AS stated i am now happy with my set up. The suspension is compliant yet roll has been reduced a lot. As I also stated I played with tire pressure and the pressure in the airbags. I do not believe they are an option in the new Winnebago View. They mounted a little strange to me. The bottom mount is on the leaf spring not the axle. The top mount is in the frame. This acts as an adjustable part of the leaf spring. Had my doubts but seems to work. They also allow you to level the rig side to side depending on your load.
One thing I forgot. I also contacted a company out of CA (the name escapes me at the moment) and had a set of wheel spacers 1.5 inches wide made. They mount in between the duallys. This widened the track of the rear a total of 3 inches. May not seem like much but adds much to the stability on the highway.
GaryJ
Here since 2006
Widening the track on a vehicle makes intuitive sense for stability, and would really help in a potential roll-over situation. But the distance between the spring perches side to side is where the body roll really takes place. That's always been the weak link in Sprinter Class C RVs with (just guessing here) spring perches that may be as much as a foot narrower than what you'd find on a domestic dually setup.
My ex 1991 E350 motorhome had the outside duals just about even with the outside edge of the 8' wide coach body. My current 2007 Winnabago View which is 7'-6" wide, overhangs the outside duals by about 5" on each side, so the spring perch width is therefor far narrower. That's the one part of the body roll equation we'll never be able to change.
Gary
Not only that, but the top shock mount is only 8.5" from center of chassis on the 3500 T1Ns. There is very little rocking control at that position. That's why shock damping needs to be so huge.
Likewise, Timbrens or Sumo springs are not so effective because they are mounted inside of the leaf springs.
BTW, I did some accelerator rocking tests on a E350 MH. It was rock solid.
Likewise, Timbrens or Sumo springs are not so effective because they are mounted inside of the leaf springs.
BTW, I did some accelerator rocking tests on a E350 MH. It was rock solid.