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Need help for continuing to modify Suspension


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We are on our last hour until Yuma and it’s been an adventure to say the least. 
 

I need some solid advise on going forward with suspension mods/upgrades.

Here is what I have:

Front: 
New Tires, Bilstien Shocks, Watts, TRW Box, Safety Steer 

Rear: 5 yr old tires, Bilstien Shocks, Cross bar

What I am thinking, and here is where I need advise 

Front, adjust the Box and ditch the safety steer. I feel like it’s always trying to center, even in curves and I lose road feel. I’m not certain my Watts is correct, and I’ll snap a pic in the morn 

Rear,

new tires go on this week, I think I need to adjust the level in the bags as she rides low now. Will the rear watts help that much with sway/road manners?

 

again, any help is great,

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JD,

I just completed a trip home from New Hampshire of nearly 1500 miles and the only driving problem was gusty winds at times. It knocks the coach sideways and of course I can feel it in the steering wheel immediately so I correct for it before it moves me into the adjacent lane.

A Steer Safe or TruCenter are no help with gusty winds. I don't have the Watts Link so not sure if that would minimize the affect of gusty winds or not. However you do so I guess the Watts link cannot mitigate that condition completely.

Frankly, my opinion is if that area of the country is experiencing massive gusty winds then it's time to get off the road until the winds subside. I was only affected a couple of times on I-26 East heading to I-95.

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Just my opinion, but I felt the rear bars actually did the most for mine, especially with movement of the coach tail.  Nothing will totally eliminate the wind issue, but that’s the last thing I did (after I removed my tru-center from steering), and the bars helped the most.

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53 minutes ago, Dr4Film said:

JD,

I thought the Watts Link was supposed to fix that? I only have problems with gusty winds.

I have front watts, not rear 

42 minutes ago, David White said:

Just my opinion, but I felt the rear bars actually did the most for mine, especially with movement of the coach tail.  Nothing will totally eliminate the wind issue, but that’s the last thing I did (after I removed my tru-center from steering), and the bars helped the most.

Thanks! You have rear watts? Talk to me about removing the true steer. What prompted you to remove it? I really feeling I’m fighting this safety steer

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I disconnected the S-T-+ until I could make it adjustable on the fly. Made driving in crosswinds tiring having to hold the steering wheel off center against it. One reason I’ll always own a S-10 chassis is the rock solid handling that makes 12+ hour days a pleasure.

A steering stabilizer seems to help the most on shorter rigs because it makes it harder to oversteer it but that’s not going to help with gusty wins where the sooner you react, the less you have to.

New tires on the rear can make for squirrley handling until they get broken end… I didn’t believe this until it happened to my 98 Beaver, especially if they are overinflated for the weight.

Edited by Ivylog
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21 minutes ago, JDCrow said:

I have front watts, not rear 

Thanks! You have rear watts? Talk to me about removing the true steer. What prompted you to remove it? I really feeling I’m fighting this safety steer

JD, the removal was actually prompted by conversations with a long time contributor/Monacoer, Bob Nodine, who determined the benefit of removal.

Bob actually was in on the original development of the front Watts idea. I always felt it made steering harder and did nothing for the driving comfort, plus I kept having issues with my unit.  It likely would help in a front tire failure.

Bob has recently purchased a Class C, but might still monitor the site and could add some insight.

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1 hour ago, David White said:

JD, the removal was actually prompted by conversations with a long time contributor/Monacoer, Bob Nodine, who determined the benefit of removal.

Bob actually was in on the original development of the front Watts idea. I always felt it made steering harder and did nothing for the driving comfort, plus I kept having issues with my unit.  It likely would help in a front tire failure.

Bob has recently purchased a Class C, but might still monitor the site and could add some insight.

You have front Watts? I need to see if mine is installed correctly. Does the center cam need to be straight up and down? 

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JD,

I have what sounds like the same setup on my RR8R chassis, with the exception of the  steering stabilizer and 'fancy' tight steering box and 'fancy' Bilstein shocks.  My steering box is an original, non adjustable and somewhat sloppy, I have no problem with that as my driving preference is to have a coach that drives straight without me having to drive it straight.

That said, I could not stand the effort required to drive my 40' monster before I installed the front Watts link and the rear cross bars.  They made it drive without changing lanes with every dip or bump in the road.  I have standard Monroe gas shocks and new tires inflated to the recommended pressure based on axle weight (weighted on CAT scales). 

One item I have that you don't is a Source Engineering Front sway bar, and I think the combination of that and the watts link is why I have very little 'push' from passing trucks. We drove across NE and WY twice last summer encountering wind warning signs of >40mph and except for having to hold some 'crab' and adjust for the gusts it was quite drivable.  Having a tire go off the edge of the pavement is no longer a 'heart attack' moment.

I recommendation to you:  ditch the steering stabilizer, add the front sway bar (mine required some modification to get the links to connect perpendicular to the chassis), adjust TP (I run my tires at about 95psi cold all around) and drive that. 

You might be happy with that, I'm considering adding the rear watts link or the rear sway bar or both because I still feel that the rear is still a bit 'loose' and the coach would ride like it was on 'rails' with the back tightened up.

 

23 minutes ago, JDCrow said:

You have front Watts? I need to see if mine is installed correctly. Does the center cam need to be straight up and down? 

No, the link, when coach a normal ride height should be at an angle, I think my link had marks on the bracket to line the link up with.

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8 minutes ago, Cubflyer said:

JD,

I have what sounds like the same setup on my RR8R chassis, with the exception of the  steering stabilizer and 'fancy' tight steering box and 'fancy' Bilstein shocks.  My steering box is an original, non adjustable and somewhat sloppy, I have no problem with that as my driving preference is to have a coach that drives straight without me having to drive it straight.

That said, I could not stand the effort required to drive my 40' monster before I installed the front Watts link and the rear cross bars.  They made it drive without changing lanes with every dip or bump in the road.  I have standard Monroe gas shocks and new tires inflated to the recommended pressure based on axle weight (weighted on CAT scales). 

One item I have that you don't is a Source Engineering Front sway bar, and I think the combination of that and the watts link is why I have very little 'push' from passing trucks. We drove across NE and WY twice last summer encountering wind warning signs of >40mph and except for having to hold some 'crab' and adjust for the gusts it was quite drivable.  Having a tire go off the edge of the pavement is no longer a 'heart attack' moment.

I recommendation to you:  ditch the steering stabilizer, add the front sway bar (mine required some modification to get the links to connect perpendicular to the chassis), adjust TP (I run my tires at about 95psi cold all around) and drive that. 

You might be happy with that, I'm considering adding the rear watts link or the rear sway bar or both because I still feel that the rear is still a bit 'loose' and the coach would ride like it was on 'rails' with the back tightened up.

 

No, the link, when coach a normal ride height should be at an angle, I think my link had marks on the bracket to line the link up with.

Great news, can you purchase just the front sway bar? If I remember correctly they (source) want to sell the whole kit, which I don’t need 

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JD

When I bought the front bar kit, the rear was not available.... I was trying to buy both..... now I'm just not sure if the rear watts or the rear sway bar is the most 'bang for my buck'... as the cross bars my be enough to hold the rear "H" frame in alinement (which is what the watts link does), and I just need a sway bar to hold the body from rolling around.... or is the "H" frame still a bit unstable, and the sway bar will not really help....   

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8 hours ago, JDCrow said:

You have front Watts? I need to see if mine is installed correctly. Does the center cam need to be straight up and down? 

JD, I don’t have my coach here to check, but my inclination is to say “yes” to the cam question. And, “no” I don’t have the rear Watts, only the rear x-bars.  I don’t think the rear Watts would do much for your problem.

I would suggest making a call direct to MonacoWatts and talk to Mike Hughes (he’s located in Lancaster CA) to get the correct answer:  monacowatts.com  

 

Edited by David White
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JD, if you already have rear X-bars, adding a Watts link in the rear will make very little difference.  I developed the whole X-Bar / Watts link system.  Bob Nodine was my first "Guinea Pig" coach.  My coach was among the last to be equipped with my devices, since I thought my coach did not wander badly enough to be a good test platform.  After installing many of the X-bar / Front Watts links, I finally added them to my own coach.  It made a huge difference, even though I had thought previously that it did not wander much.

Adding the front Watts link makes a large difference.  NO, the Watts lever need not be perfectly vertical.  It performs just as well with the Watts lever +/- even 20 degrees.

The anti-sway bar may have some benefits, but stopping wandering is not one of them.  Bob Nodine can confirm that.  He installed them front and rear to cure his wandering.  It had little to no effect.

Bob Nodine and I both removed our S-T-+ hydraulic stabilizer.  I'm not knocking it.  Both of us felt it just added to much effort to steering.  And NO device like that, adjustable or not, will mitigate GUSTING winds...and how often are winds consistent in speed and direction?

I think you have done most of the things to improve your coach's handling.  Are you still dissatisfied?

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46 minutes ago, vanwill52 said:

JD, if you already have rear X-bars, adding a Watts link in the rear will make very little difference.  I developed the whole X-Bar / Watts link system.  Bob Nodine was my first "Guinea Pig" coach.  My coach was among the last to be equipped with my devices, since I thought my coach did not wander badly enough to be a good test platform.  After installing many of the X-bar / Front Watts links, I finally added them to my own coach.  It made a huge difference, even though I had thought previously that it did not wander much.

Adding the front Watts link makes a large difference.  NO, the Watts lever need not be perfectly vertical.  It performs just as well with the Watts lever +/- even 20 degrees.

The anti-sway bar may have some benefits, but stopping wandering is not one of them.  Bob Nodine can confirm that.  He installed them front and rear to cure his wandering.  It had little to no effect.

Bob Nodine and I both removed our S-T-+ hydraulic stabilizer.  I'm not knocking it.  Both of us felt it just added to much effort to steering.  And NO device like that, adjustable or not, will mitigate GUSTING winds...and how often are winds consistent in speed and direction?

I think you have done most of the things to improve your coach's handling.  Are you still dissatisfied?

It seems any wind will push the coach, and really hard to regain control. It’s a constant push to keep it against coming from the side winds, and I had head wind that just just made the front wander uncontrollably. 
 

I’ll start by pulling off the safety steer. And Van I believe you have outlined in the past how to adjust the lash out of the TRW box. I believe though the nut was torqued on with a multiplier and not sure I’ll get it off. I have a 3 hour drive Wednesday to Havasu, and it’s windy so it will be a good test for that 

 

Thanks all, I’ll keep updating fixes and results.  We are half heartedly calling Pearl, our “Rolling Breadbox of Death” now. I’d like to get that name erased 

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JD, I have never found the 3/4 hex locknut on dozens of TRW boxes I've adjusted to be too tight to get loose.  Often, however, the locknut is rusted to the adjustment screw, and some serious back-and-forth is required to break them loose from one another.  To get an accurate adjustment, the locknut and adjusting screw must be very freely turning.  You MUST have the steering gear witness marks aligned to adjust the gear (wheels straight ahead).  If your steering gear has any significant play, gusting winds or passing tractor-trailers will be a handful.

Check your Watts link and X-bars for any indication that the mounting plates are moving, or something is loose.  Check for any deterioration in the bushings at the ends of the trailing arms (4 front and 4 rear).  You almost surely have the one-piece later design of bushing, so unless something odd has happened, they should be OK.

I was in a caravan of five coaches leaving from the southeast to Alaska in 2016.  Four of the coaches had my prototype rear X-bars and front Watts links.  We went through some truly brutal gusting winds in Nebraska (white caps on the drainage ponds along the Interstate) which the radio reported were gusting to over 40 MPH.  EVERYONE remarked how stable their coaches were, even when being passed by semi's.  2000 Dynasty 36 (mine), 2006? Diplomat 40 (Bob Nodine), 2011 Camelot 45 (Tom Moore--only tag-axle in the group), 2013 Knight (Craig French).

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JD,

Is your front watts link mounted forward or aft of the 'H' frame?   The only thing I have that you do not have is the front sway bar.  I did not have much problem with the strong and gusty winds last summer in NE and WY and I have a 40' bread box..... Prior to adding the watts link and rear crossbars and front sway bar my coach was all over the road, any bump, any seam, overpass seams, passing cars and trucks sent it is any direction.....   

As Van W suggested, check your suspension for looseness.  If ok, I would suggest you add the front sway bar.  It should tame the side to side rocking (I used to have a bad case of that) which should help a lot in crosswinds.

I would not spend a lot of time and energy trying to 'tighten up' your steering box.... that steering wheel thing is to guide the coach to go where you want it to go, not keep it going straight and steady on the road, that's the suspension's job......  JMHO 

Edited by Cubflyer
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4 hours ago, vanwill52 said:

JD, I have never found the 3/4 hex locknut on dozens of TRW boxes I've adjusted to be too tight to get loose.  Often, however, the locknut is rusted to the adjustment screw, and some serious back-and-forth is required to break them loose from one another.  To get an accurate adjustment, the locknut and adjusting screw must be very freely turning.  You MUST have the steering gear witness marks aligned to adjust the gear (wheels straight ahead).  If your steering gear has any significant play, gusting winds or passing tractor-trailers will be a handful.

Check your Watts link and X-bars for any indication that the mounting plates are moving, or something is loose.  Check for any deterioration in the bushings at the ends of the trailing arms (4 front and 4 rear).  You almost surely have the one-piece later design of bushing, so unless something odd has happened, they should be OK.

I was in a caravan of five coaches leaving from the southeast to Alaska in 2016.  Four of the coaches had my prototype rear X-bars and front Watts links.  We went through some truly brutal gusting winds in Nebraska (white caps on the drainage ponds along the Interstate) which the radio reported were gusting to over 40 MPH.  EVERYONE remarked how stable their coaches were, even when being passed by semi's.  2000 Dynasty 36 (mine), 2006? Diplomat 40 (Bob Nodine), 2011 Camelot 45 (Tom Moore--only tag-axle in the group), 2013 Knight (Craig French).

Thanks, if the witness marks are not aligned, then I’ll need to drop the linkage?

46 minutes ago, Cubflyer said:

JD,

Is your front watts link mounted forward or aft of the 'H' frame?   The only thing I have that you do not have is the front sway bar.  I did not have much problem with the strong and gusty winds last summer in NE and WY and I have a 40' bread box..... Prior to adding the watts link and rear crossbars and front sway bar my coach was all over the road, any bump, any seam, overpass seams, passing cars and trucks sent it is any direction.....   

As Van W suggested, check your suspension for looseness.  If ok, I would suggest you add the front sway bar.  It should tame the side to side rocking (I used to have a bad case of that) which should help a lot in crosswinds.

I would not spend a lot of time and energy trying to 'tighten up' your steering box.... that steering wheel thing is to guide the coach to go where you want it to go, not keep it going straight and steady on the road, that's the suspension's job......  JMHO 

I’ll crawl under in the morn. Just got done with a date shake and some Canes chicken strips with Texas toast and I’m down for the count. I’ll report in the morn 

F6F67134-4458-4D63-A0E0-3B754D18D3DA.jpeg

Edited by JDCrow
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4 minutes ago, Scott 61 said:

I have an 08 Holiday Rambler Endeavor RR8R  Was thinking about getting the Watts link & crossbar what I'm reading I only need the front Watts Link & rear cross bars & front sway bar is that correct?? thank you 

Scott, based on all I’ve read and my experience, I would do the 2 you had planned and wait on the sway bars.  Likely you will see a good improvement without the sway bars, but can always add later if required.

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7 hours ago, David White said:

Scott, based on all I’ve read and my experience, I would do the 2 you had planned and wait on the sway bars.  Likely you will see a good improvement without the sway bars, but can always add later if required.

I agree with David that you do the front Watts link and rear crossbars and wait on he sway bars. 

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9 hours ago, JDCrow said:

Thanks, if the witness marks are not aligned, then I’ll need to drop the linkage?

I’ll crawl under in the morn. Just got done with a date shake and some Canes chicken strips with Texas toast and I’m down for the count. I’ll report in the morn 

F6F67134-4458-4D63-A0E0-3B754D18D3DA.jpeg

Van beat something into my head and I think everyone needs to keep that lesson in mind. It is a simple statement, "your coach is going to go where your wheels are pointed". If gusting winds are changing the direction of your coach then the wind pushing against your coach is changing the direction that the front wheels are pointing. The design of the Roadmaster chassis makes it almost impossible to completely stop this because the wheels are floating on four air bags that must be stabilized by trailing arms and a single Panhard bar. The Watts link makes a huge difference because it removes the tendency of the H-frame to twist on the fulcrum point created by having only one Panhard bar. That is why it is important to keep the Watts link as far from the Panhard bar as possible. If the Watts link is mounted on the same side of the H-frame as the Panhard bar then it will not be as effective in keeping the H-frame from twisting when trucks pass or a gust of wind hits the side of the coach. The trailing arms are long and that coupled with the fact that bushings must have some give makes it impossible for the trailing arms to completely stabilize the H-frame. I don't know the relationship of your Watts link to your Panhard bar but I suspect that it is either not far enough away or your Watts link is not firmly attached or has a loose or broken pivot pin. Just 1/16 of an inch of movement will affect the straight line handling of the coach.

This brings up the subject of the TRW and the tie rod ends. Any slop in the tie rod ends or movement of the Pitman arm on the TRW will cause the front wheels to change direction when wind pushes against the side of the coach. Remember your coach is going where your wheels are pointed. I could bore you with some trigonometry of what will happen at 60 MPH if your font wheels slightly change direction but I want. 

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Source Engineering has “Comfort Ride Valve Kit” that restricts air out of the airbags helping to reduce roll. A lot easier to install than a roll bar.

Newer rigs have “ping tanks” that help to decrease roll by increasing the volume of air.

No offense to short wheelbase rigs BUT their better turning radius hurts their straight line control compared to longer rigs.

0E7441FB-DC28-4637-B17B-EC9653FFB86E.png

Edited by Ivylog
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What Bob Nodine said about the steering gear needing to have minimal play to minimize wandering is correct.  If you jack up your rig's front tires off the ground (DON'T let it hang on the shocks), you can grab the tire and move the front wheels back and forth.  That demonstrates that the steering gear has very low internal friction and is easily moved by even a small outside force.  When a side force acts on the coach, it tends to cause the front wheels to want to change direction (in addition to trying to "twist" the H-frame, which also changes your wheels' direction).  If the caster was set at zero, this effect would be minimized, but positive caster is necessary for the coach's wheels to have a natural tendency to "return to center" after you make a turn.  Were it not for caster, you would have to crank the wheel back to center.

Even in the TRW gear (just as in the Sheppard) the Pittman arm is driven by a purely mechanical rack-and-pinion.  When you turn the steering wheel (through a low-friction ball screw and nut) you are moving the rack.  The rack, in turn, causes the pinion to rotate.  The pinion is rigidly attached to the Pittman arm which (through linkage) turns the wheels back and forth.

The genius of the TRW gear design, as opposed to the Sheppard, is that the rack gear (mounted to the ball nut inside the gear) is cut with "crowned teeth".  That is, the teeth are "higher" (greater pitch diameter) in the middle (the dead-ahead position).  The "dead ahead" position is where most of the wear occurs on both the pinion and the rack, since you spend the great majority of your time driving in a nearly straight line (down a straight highway, for instance).  Since the center is the position where the maximum wear will occur, if you could increase the size (pitch diameter) of the pinion, you could compensate for that wear.  Fortunately, the TRW gear is equipped with a pinion whose teeth are cut in a "cone shape". That is, the pitch diameter increases (very slightly) along its tooth length.  The adjustment on the TRW gear allows you to increase the engagement of the pinion gear into the rack gear, increase the pinion's effective pitch diameter, and decrease the backlash to near-zero.  This works only because the rack gear is cut with its teeth higher in the middle.  Were that not the case, if you increased the engagement of the pinion to compensate for wear of the rack gear in the "straight ahead" position, it would bind as it traveled to either side of center.

This is the reason that a Sheppard gear CANNOT be "blueprinted" by ANY method to have near-zero backlash EXCEPT by sorting through parts to find the largest pinion and rack that will fit together.  There is NO adjustment for depth-of-engagement of the pinion to the rack gear.  Then, over time, backlash will grow in the "straight ahead" position and nothing can be done about it.  The Sheppard has a straight-cut rack and a straight-cut pinion.  To its credit, the Sheppard gear is significantly more rugged than the TRW, and that is perhaps why it is the steering gear of choice on many heavy off-road vehicles, where travel speeds are low and "straight ahead" backlash is of little consequence.

The reason that Sheppard gears perform OK in road tractors is that the front axle of the tractor is orders of magnitude more stiffly connected to the truck chassis through heavy leaf springs.  Therefore, the tendency of the wheels to remain "dead ahead" is much greater than our coaches with axles connected to separate H-frames connected by spindly trailing arms and supported by mushy air bags, and held in position by ONE Panhard rod, before connecting to the coach chassis.  Add to that the tendency of multi-axle vehicles to continue in a straight line in the face of side forces, and you have a case where the "dead ahead" backlash is of little consequence.

The tendency of tag-axle coaches to exhibit much less tendency to wander is due to this multi-axle tendency to move in a straight line.  It is also the reason that most coach manufacturers advise you to lift the tag axle when attempting to make sharp turns at low speeds.

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