Need help for continuing to modify Suspension

[Paul J A]

WOW!

[JDCrow]

20 minutes ago, Ivylog said:

One person posted a drive axle of 17,000 lbs but mine is 23,000 lbs…a 6,000 lbs difference and why I’d be dragging the hitch. Also, you couldn’t adjust the amount the tag supports.

All good. Just trying to point out there are other suspension that will carry weight that are not air bag based. 
 

[pwhittle]

On 10/27/2021 at 7:38 PM, Ivylog said:

Has anyone put a Watts link on a S-10’s front axle? I would love to drive it to see what I’m missing.

Dick,

I have a front Watts Link on an S-10 chassis.

Paul

[Cubflyer]

On 10/27/2021 at 9:56 PM, JDCrow said:

Really hunting the road left and right. After I took truck off, it was better, still not solid, but better it took less effort to keep it between the lines. 

JD,

You now have the same set-up,  (watts link, sway bar in the front and cross bars in the rear) as I have on my coach which is a 40'  (vs 34').... The only difference is your steering box... mine is not adjustable and quite loose.  You also have said that you adjusted your steering box..... could you have gotten it too tight?  and sensitive? 

With the watts and the cross bars, tires shocks and sway bar in front, my coach runs true down the road even with wind and passing trucks.... seems like yours should be pretty solid too.  How many miles do you have on the chassis? I'm just over 70k... and a couple of years younger.... maybe your drag and pan hard bushings are soft..??

Ken

 

[JDCrow]

9 minutes ago, Cubflyer said:

JD,

You now have the same set-up,  (watts link, sway bar in the front and cross bars in the rear) as I have on my coach which is a 40'  (vs 34').... The only difference is your steering box... mine is not adjustable and quite loose.  You also have said that you adjusted your steering box..... could you have gotten it too tight?  and sensitive? 

With the watts and the cross bars, tires shocks and sway bar in front, my coach runs true down the road even with wind and passing trucks.... seems like yours should be pretty solid too.  How many miles do you have on the chassis? I'm just over 70k... and a couple of years younger.... maybe your drag and pan hard bushings are soft..??

Ken

 

I thought the same and readjusted the steering back “looser”. Really didn’t make a difference. My short wheelbase I believe compounds things. We both share the same amount of weight from the back axle to the rear. Your 40 can act as a big lever and put weight out farther,  and mine cannot. 

I mentioned that I’m getting an alignment Monday, and hopefully it will answer some questions. I’m also going to invest in the rear Watts, and maybe the rear sway. Looking at the instructions for both, each will sit on opposing sides of the rear axle. Between all securing of front and rear H frames maybe I can get straight!

One thing on the rear sway bar that has me scratching my head. I’ve driven my fair share of class 8 trucks, and had repairs, but one thing that was never ever done was drill into the top or bottom of the C channel on a truck frame. You can put holes in the sides, but the top and bottom and your asking die cracks. 
 

It looks like the source kit drills 2 holes in the bottom of the C channel frame

http://sourcerv.com/1169-209.pdf
 

Any thoughts?

[Cubflyer]

Looks like they are relatively small holes and they are sandwiching the frame between two plates which should spread the stress out. Use a step drill and or ream and debur the holes if you are really concerned....

Ken

[JDCrow]

3 minutes ago, Cubflyer said:

Looks like they are relatively small holes and they are sandwiching the frame between two plates which should spread the stress out. Use a step drill and or ream and debur the holes if you are really concerned....

Ken

7/16 

It is interesting that on the sway bar, the attachment point in down on the axle, but the rear, ( for obvious reasons, there’s no bolts on the axle) is the H-Frame itself. 

[Ivylog]

8 hours ago, pwhittle said:

Dick,

I have a front Watts Link on an S-10 chassis.

Paul

Hopefully it might be in the Bville area…would love to drive it. How much of a difference did the Watts make. From the sounds of things if I had the Watts, I could put the cruise on and get up and go to the bathroom.

[vanwill52]

7 hours ago, JDCrow said:

I thought the same and readjusted the steering back “looser”. Really didn’t make a difference. My short wheelbase I believe compounds things. We both share the same amount of weight from the back axle to the rear. Your 40 can act as a big lever and put weight out farther,  and mine cannot. 

I mentioned that I’m getting an alignment Monday, and hopefully it will answer some questions. I’m also going to invest in the rear Watts, and maybe the rear sway. Looking at the instructions for both, each will sit on opposing sides of the rear axle. Between all securing of front and rear H frames maybe I can get straight!

One thing on the rear sway bar that has me scratching my head. I’ve driven my fair share of class 8 trucks, and had repairs, but one thing that was never ever done was drill into the top or bottom of the C channel on a truck frame. You can put holes in the sides, but the top and bottom and your asking die cracks. 
 

It looks like the source kit drills 2 holes in the bottom of the C channel frame

http://sourcerv.com/1169-209.pdf
 

Any thoughts?

JD, the anti-sway bar will not make any difference in the wandering.  It has no ability to stabilize the H-frame, due to the links that connect it to the frame.  You may find other reasons for liking it, but it will not help your wandering problem, except between your ears, since you will pay a lot of money for it.

Try getting your Watts link lever more vertical.  I cannot imagine a reason that would make any difference--just grabbing at straws, because I cannot imagine why you are having the problem.  I think the only definitive difference you can make at this point is to move your Watts link further from the Panhard rod.  That involves reinforcing your genny supports and cross-bracing them.  I'll send pix if I have time.  Getting ready to take my wife to a specialist in Atlanta for her Trigeminal Neuralgia.

[pwhittle]

3 hours ago, Ivylog said:

Hopefully it might be in the Bville area…would love to drive it. How much of a difference did the Watts make. From the sounds of things if I had the Watts, I could put the cruise on and get up and go to the bathroom.

It was not as significant improvement as our 1994 Sig - non Tag, but I could sense an improvement.

Paul

[JDCrow]

2 hours ago, vanwill52 said:

JD, the anti-sway bar will not make any difference in the wandering.  It has no ability to stabilize the H-frame, due to the links that connect it to the frame.  You may find other reasons for liking it, but it will not help your wandering problem, except between your ears, since you will pay a lot of money for it.

Try getting your Watts link lever more vertical.  I cannot imagine a reason that would make any difference--just grabbing at straws, because I cannot imagine why you are having the problem.  I think the only definitive difference you can make at this point is to move your Watts link further from the Panhard rod.  That involves reinforcing your genny supports and cross-bracing them.  I'll send pix if I have time.  Getting ready to take my wife to a specialist in Atlanta for her Trigeminal Neuralgia.

Yeah I know it won’t help the wandering. I will be getting a rear watts when I get home. 
 

I do like the way the coach doesn’t roll in turns, and it’s bouncing is minimized with the front sway bar, so the rear should stiffen up the roll. 
 

Really at this point. I’m wishing I had the read outs from the first alignment. I’m anxious to get this in on Monday and see if there is anything just glaring at this point. If not, we Will nurse it home and move the front Watts and work on the rear 

I appreciate you taking time out for me, please take care of your wife, and yourself. I wish a resolution, or at least some relief from her pain. 
 

JD

[vanwill52]

17 minutes ago, JDCrow said:

Yeah I know it won’t help the wandering. I will be getting a rear watts when I get home. 
 

I do like the way the coach doesn’t roll in turns, and it’s bouncing is minimized with the front sway bar, so the rear should stiffen up the roll. 
 

Really at this point. I’m wishing I had the read outs from the first alignment. I’m anxious to get this in on Monday and see if there is anything just glaring at this point. If not, we Will nurse it home and move the front Watts and work on the rear 

I appreciate you taking time out for me, please take care of your wife, and yourself. I wish a resolution, or at least some relief from her pain. 
 

JD

I don't understand why you are having a problem, but adding a rear Watts link, in addition to your X-braces, is unlikely to make any difference.  You would likely get more improvement from moving your front Watts link further from the Panhard bar.  If you have any way of doing so, check for looseness in the Panhard rod and trailing arm bushings.

[JDCrow]

11 minutes ago, vanwill52 said:

I don't understand why you are having a problem, but adding a rear Watts link, in addition to your X-braces, is unlikely to make any difference.  You would likely get more improvement from moving your front Watts link further from the Panhard bar.  If you have any way of doing so, check for looseness in the Panhard rod and trailing arm bushings.

Ok, will have a good shake down Monday. Bro, take care of your wife, I’m ok here. Thanks very much, I’ll keep posting how things are going. 

[Bob Nodine]

21 hours ago, JDCrow said:

Ok, will have a good shake down Monday. Bro, take care of your wife, I’m ok here. Thanks very much, I’ll keep posting how things are going. 

JD,

I ran the front and rear sway bars on our 2006 Diplomat for 13 years and never had any problem from the way they were mounted. The sway bars were the second thing I did in my quest to improve the handling of the coach.

On your coach have you looked real close in the rear for broken welds? If there is a broken weld that will allow movement of the rear axle then taking the truck off would make a difference. Often towing a vehicle reduces wandering but in your case it seems to exacerbates it.

Bob

 

[Bob Nodine]

On 10/29/2021 at 6:36 AM, Ivylog said:

Hopefully it might be in the Bville area…would love to drive it. How much of a difference did the Watts make. From the sounds of things if I had the Watts, I could put the cruise on and get up and go to the bathroom.

An advantage of the Dynasty and above coaches often overlooked is the rigidity of the chassis. Because the motorhome structure is a steel frame welded to the frame the frame is very stable and does not flex. When we purchased the 2006 Diplomat it was only a year old and I think it was traded in because it handled so poorly. The ride height was way off and when we would hit a dip in the road the bathroom door would fly open. Being a newbie to the motorhome scene I did not understand what was going on but later understood that the frame was flexing. After getting the ride height adjusted the bathroom door did not fly open. Still when driving on the interstate and getting hit by a gust of wind or passed by a semi the coach would jump a foot in the lane. Very unnerving. That is why we spent so much time and effort on the Watts link. So besides the tag axle you have the stiff frame in your corner of the ring. If you pay much attention to the forums you will notice that the folks who are always complaining about wandering and handling are those who own the non tag and non S-frame Monaco coaches. Another downside to these Indiana built coaches is they usually have a Shepard steering sector that has lots of dead motion. It would be nice if everyone could own a coach like you have but that is not always the case. Even the lower end Monaco coaches have a well built house with nice cabinets and often folks are sucked in by the eye candy and the quality of the coach. Once they purchase the coach they love everything about it except driving it on the interstate in windy conditions. You may not see the value of the Watts link or the cross bars because they add little improvement to the Dynasty and above coaches. They make a world of difference on the lower end coaches.

[JDCrow]

2 hours ago, Bob Nodine said:

JD,

I ran the front and rear sway bars on our 2006 Diplomat for 13 years and never had any problem from the way they were mounted. The sway bars were the second thing I did in my quest to improve the handling of the coach.

On your coach have you looked real close in the rear for broken welds? If there is a broken weld that will allow movement of the rear axle then taking the truck off would make a difference. Often towing a vehicle reduces wandering but in your case it seems to exacerbates it.

Bob

 

I’ve been all over this thing, and my mind never shuts off trying to figure it out.

You mentioned right height in a post above. I’ve remarked in the past that I don’t think there is enough weight on the front axle. (A little over 8K)

Looking at it when it’s aired up it looks tail low or front high. I want the shop to check it when it’s in on Monday.

Another thing that’s been bugging me; did the guys who put my TRW on do the proper procedure to engage the poppets? Is the pump staying “on” and keeping pressure at full charge when I engage the steering wheel one way or the other? So Monday morn I’ll lift up the Dip and turn it lock to lock, just for kicks 

[JDCrow]

Just picked up from the alignment shop. Brought the toe in slightly. They claimed my front end caster cannot be adjusted? 
 

I asked them to raise the ride height. I did a quick, But not level measurement before we left Grand Canyon and it appeared to be about 1” low in front and 1 1/2-2” low in the back. I don’t think them knew exactly what they were doing and just pushed the rods up a “half inch” and said they were topped out. 
 

I did another quick measurement at the park at staying at and again it’s not level but it appears to be closer to where it needs to be. The tec must have never seen a safety steer as he claimed I had a bad tired causing the pull. Tires are new with 1000 miles on them or so. 
 

Anyway, it drove better on I-40 through town, I bumped the safety steer and will see tomorrow as we head north if we have improved 

[Dr4Film]

10 hours ago, JDCrow said:

They claimed my front end caster cannot be adjusted?

I asked them to raise the ride height. I did a quick, But not level measurement before we left Grand Canyon and it appeared to be about 1” low in front and 1 1/2-2” low in the back. I don’t think them knew exactly what they were doing and just pushed the rods up a “half inch” and said they were topped out.

As Van stated earlier the front axle would need to be bent to adjust camber. If they are not equipped to do that then they are using the excuse above.

Once ride height is adjusted correctly, you should be able to take the coach to a level parking lot and measure from the ground to the bottom of the belt-line directly in the middle of each tire/wheel. Those measurements should be close and the coach should look level.

Edited November 2, 2021 by Dr4Film
Change Caster to Camber

[JDCrow]

1 minute ago, Dr4Film said:

As Van stated earlier the front axle would need to be bent to adjust caster. If they are not equipped to do that then they are using the excuse above.

Once ride height is adjusted correctly, you should be able to take the coach to a level parking lot and measure from the ground to the bottom of the belt-line directly in the middle of each tire/wheel. Those measurements should be close and the coach should look level.

Ok I’ll fuel up in the morn and that should be a level pad. 
 

I was measuring the dimensions from the manual, 9.5 front and 11.5 rear from top of H frame to bottom of frame rail. 

[Cubflyer]

19 minutes ago, JDCrow said:

They claimed my front end caster cannot be adjusted? 

Caster is the fore and aft tilt of the kingpins.... angle is built into the axle mounting pads, it's relationship to the ground can only change by changing it's mounting to the "H" frame... so it could be adjusted, without bending things..... not sure why they would say it's not adjustable, it just should not need to be adjusted... 

Did they give you and specifications? Or what the caster and camber angles were?... sure they adjusted the toe, but to what?? What was it and what is it now...? 

When you are trying to troubleshoot something it's good to have data... but they probably did not give you any..

 

[Dr4Film]

Here is a great explanation of solid axle alignment.

https://www.motortrend.com/how-to/0902sr-science-of-straight-axles/

[JDCrow]

On 11/1/2021 at 7:00 PM, Cubflyer said:

Caster is the fore and aft tilt of the kingpins.... angle is built into the axle mounting pads, it's relationship to the ground can only change by changing it's mounting to the "H" frame... so it could be adjusted, without bending things..... not sure why they would say it's not adjustable, it just should not need to be adjusted... 

Did they give you and specifications? Or what the caster and camber angles were?... sure they adjusted the toe, but to what?? What was it and what is it now...? 

When you are trying to troubleshoot something it's good to have data... but they probably did not give you any..

 

Yeah they only said toe in 1/8”  I’m not sure it was the most technical of places 

17 hours ago, Dr4Film said:

Here is a great explanation of solid axle alignment.

https://www.motortrend.com/how-to/0902sr-science-of-straight-axles/

Awesome, I have been trying to go back and re-read certain aspects as it relates to me. I found something interesting:

“One of the most common mistakes when setting caster is making the adjustment while the chassis is not at ride height front and rear. Caster is the relationship of the axle to the ground, not the chassis. That means if it's set at 5 degrees positive with the frame sitting level on a jig, then the car is put on the ground with a 3 degree nose-down rake, the caster will be 2 degrees positive-and you'll be wondering why the car wanders all over the road”

I was not able to get a flat spot to measure the belt line today, but whatever amount it was raised up, made a huge difference in handling today. 

I’ll post here in a bit 

 

[JDCrow]

So today was a sigh of relief. Last night after paying for the alignment, I was mad. I told my wife I was going to torch the Dip, she said “let me get my stuff out first”

Well the drive to the RV park, it was noticeably improved in the squishy/wandering feel. 
 

I hooked up the Raptor, not sure what to think, prepared for another exhausting day. I was surprised. The effort to keep the Dip in the lane was diminished. While it’s not perfect, it took smaller movements on the wheel, and it was comfortable to drive at 60 mph. 
 

Wind was lower, so that helped, but even in town this thing was a mess. I see light now. So ride height seems to be helping.

I believe the rear of the Dip needs tightened up still. She gets loose when I head downhill, especially with the toad on. It feels safer either under power with throttle or with the jake holding her back. I’ll move the Watts on the front as Van recommend and it should help with the last of the wander up front.

I’m thinking at 20 yrs old in Feb, the right height and stability could be further improved with new air bags. Just having the coach up, and I don’t know how much, made a big difference, and I’m looking forward to getting it all wrapped up. Thanks everyone for your encouragement and help

 

Edited November 3, 2021 by JDCrow

[Cubflyer]

Great photos!

IMHO replacing air bags will do nothing, unless they are leaking and not holding air.  The ride height is controlled by air valves.  With an unlimited supply of air the only reason the valves would not control the ride height is if the lines or airbags leaks exceed the volume capacity of the valves..... not likely (it would not be a subtle leak).

The beltline measurement is a good idea for a rough idea of your ride height but you rally need to set the height with measurements between the points given in the manual (between frame and H frame or airbag mounting points?) as there can be much more than 1/4"-1/2" difference in ground surface on even the flattest ground.  I believe the specs on the ride height are within 1/8"-1/4"  (been a long time since I looked at mine).

Sounds like you are on the right course and will get there.

Ken

[JDCrow]

3 hours ago, Cubflyer said:

Great photos!

IMHO replacing air bags will do nothing, unless they are leaking and not holding air.  The ride height is controlled by air valves.  With an unlimited supply of air the only reason the valves would not control the ride height is if the lines or airbags leaks exceed the volume capacity of the valves..... not likely (it would not be a subtle leak).

The beltline measurement is a good idea for a rough idea of your ride height but you rally need to set the height with measurements between the points given in the manual (between frame and H frame or airbag mounting points?) as there can be much more than 1/4"-1/2" difference in ground surface on even the flattest ground.  I believe the specs on the ride height are within 1/8"-1/4"  (been a long time since I looked at mine).

Sounds like you are on the right course and will get there.

Ken

Thanks for advise. I’m a little worried about the air bags may have been sitting deflated for years, as I know the coach was sitting. I don’t know if they loose flexibility or if internally rubber deteriorates or cords become detached? The bags do loose air overnight. The coach takes days to lose air. My dump valve for the bags doesn’t work either 

I look at where we are at, and I’m waist deep already. If I can start getting as much stiffened up as I can, then I’ll be a happy camper. 
 

Along that line, the trailing arms; is there a polly bushing replacement?