Improving The Ride - Recommendations?

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My statement stands. I don't knowhow your springs are connected. The test is how the load is carried. If all of it is carried by each spring they are in series and, for equal springs the deflection is doubled. In parallel the load divides and deflection is reduced so stiffness is increased. Deflection due to load is directly indicative of stiffness.
 
Ernie n Tara said:
My statement stands. I don't knowhow your springs are connected. The test is how the load is carried. If all of it is carried by each spring they are in series and, for equal springs the deflection is doubled. In parallel the load divides and deflection is reduced so stiffness is increased. Deflection due to load is directly indicative of stiffness.
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Are we saying the same thing?  The SumoSpring is placed between the frame and the leaf spring thus it would be parallel and would increase stiffness.  The only wrinkle is their web site states it offers progressive resistance so maybe the stiffness is not encountered unless compressed more than what happens during normal road conditions.  Granted there would have to be some additional stiffness but that may be minimal compared to gains from the shock replacement?

Anxious to hear from some who have gotten rid of the OEM shocks.  Problem is it is always subjective and not by anyone who has instrumentation that can actually measure it.
 
the correct answer is "C"... the way springs are measured is amout of force to compress 1" so if you ave two 300lb stacked.. 300 lbs will compress the stack 2''  1'' wil compress at 150 lbs...

to fully understand sumo's way of working you have to know about springs.... if you measure from the top of the wheel well to the ground at ride hight, then jack up the front  till the tire is just touching... that's suspension droop...now let it back down and measure from the top of the axel to the bump stop (where the bump hits the axel)and add the droop, that's you total wheel travel...

to further put a number you would have to compress the spring 1'' to see the spring rate... and know the progression rate... standard on a 300 lb spring is 1"=300lb... 2'' = 600 3"= 1200...

so lets say you have 50% droop... more is better for bumpy/off road...now you add the sumo...what the sumo does is slows down the progression from ride hight to full compressed..and speeds up the spring on rebound..so now you hit the next bump with more suspension...
next, what happens when shocks are valved tooo stiff first IT takes too much bump to compress the shock...and now to add to that if the rebound is not right.. the shock is still compressed when it hits the next bump...bamm  ,that's called packing... now the only suspension you have is the cushion of the tire...

so rather than fix whats wrong... people lean to letting air out of the tire to soften the ride... not good..less air causes tires to "WALK"... which in turn causes sway...and causes destruction of the tire and rim... off course you have to have the correct amount of air to carry the weight..

now that being said....when adding sumo's , to get the best performance... you have to get the right color (durometer) for your coach..

I used my coach to carry heavy toung weight, that and add 158'' wheel base.. so I went with the stiffest..I install sumo's to be 1/2'' compressed to get the best performance
 
Gregg said:
I am anxiously watching this for some additional feedback on the Sumosprings.  Having a difficult time understanding how a product that is supposed to increase load capacity actually improves the ride.  Is the improvement in how the RV handles potholes and rough roads or body roll?  Just got back from a trip where there was a lot of highway construction going on and the ride was let's say not very relaxing nor desirable. 

I personally installed the Safe-T-Steer on my F53 and would say that it took the jarring out of the steering.  For example, I used to feel some feedback when pulling into my driveway.  We have those concrete gutters at the end of the drive which seemed to cradle the 19.5" wheels or something.  That is now gone so I am sure it helps out on the ruts and pot holes on the open road.
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a little some thing I know for fact... the only difference between the 16k and 18k chassis is the springs... so if you change out the springs you have an 18k chassis.. may not be fed rated... but you get the point..
 
My first question is what is that video talking about how maintance  on a air bag system is so high, and they have so many problems? The ones on my MH have required nothing more than a inspection, and the ones on my 3500 the same? If installed right and used right where is the big problem?

my second question if you stack 2 300lb springs on top of one another and apply 300lbs to them do they compress 1inch each? so a total of 2"?
 
kevin said:
My first question is what is that video talking about how maintance  on a air bag system is so high, and they have so many problems? The ones on my MH have required nothing more than a inspection, and the ones on my 3500 the same? If installed right and used right where is the big problem?

my second question if you stack 2 300lb springs on top of one another and apply 300lbs to them do they compress 1inch each? so a total of 2"?
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yes total of 2'' if one spring is too stiff adding a second will make the ride softer and increase sprung wheel travel..

as far as air bags, the only work one direction and as you turn the insidee compresses and the outer expands
 
Sorry! The correct answer is 600 lb./In. (a as I recall). Your description of the series spring operation is correct  but the deflection of two 300 lb./in. springs in paralled is 0.5 inches under a 300 lb. load or 600 lb./in.

The fact that your springs are progressive increases the deflection but it will still be less than an inch.

Ernie

 
Isn't the harshness of ride we are experiencing a resistance to the inertia that the tires, springs, and shocks do not absorbed through deflection or compression when hitting a pot hole or rough surface?

Setting aside your suspension bottoming out, I am really having difficulty understanding how you can add another spring that supposedly reduces deflection under load and doing so without increasing an opposing force. Wouldn't that make it a harsher ride during normal road conditions or when the springs are not compressing significantly?  Suppose that the Sumo are progressive but you would still have to sacrifice some during normal road conditions.

Interesting topic.  Thinking my first investment to improving the ride will be to replace the OEM Belstein shocks.  Moving up to 22.5" rims and a larger diameter tire are way out of the budget.

 
Gregg said:
Setting aside your suspension bottoming out, I am really having difficulty understanding how you can add another spring that supposedly reduces deflection under load and doing so without increasing an opposing force all without making it a harsher ride.

Isn't the harshness of ride we are experiencing a resistance to the inertia that the tires, springs, and shocks do not absorbed through deflection when hitting a pot hole or rough surface?
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the best way to see whats going on ,...a go-pro... you can see and feel the difference..the correct answer is "C"150lbs..if you put a 300 lb coil spring on top of a 300 lb spring....  150lbs will compress the springs  one inch making the spring rate 150 ...
hard to explain with out showing you on a spring compressor...we set up off road cars at my shop, and valve shocks..I was involved with coming up with a new shock that was valved correct for the f53 chassis and for motorhomes in general... but ...the best we came up with was just a pretty much a copy of the road kings.. so I pulled out and figured to just buy a set of road kings and re valve them as needed...

an easy way to test the correctness of my statement , and you can do this at home... put a scale(house) on top of a floor jack... then put a known 100lb spring on it..., I slide the floor jack under the tongue of my trailer..measue the spring, with it on the scale ,jack it up one inch... and look at the scale  should read 100 lbs... now.. stack another spring on top... and jack it up ,...should read only 50lb  so to gether you only have a 50lb spring...thtas just the basics...on my cars some times i'll run a 100 over 300.. and put a cross over collar to tune the suspension to where I want it...

but like I said...to find out if people even know basic springs, how they are measured and rated I always ask this question...most get it wrong...or just wanna argue with the sign post and take the wrong road home....I just send them on there way and wave bye bye....

the way sumo's work, they change the progression of the leaf spring to result in a softer ride, they also work better to control body roll as they work compressed ., or stretched..of course to get the best out of sumo's , you have to pick the right durometer bag.. although , most are happy with the kit sumo supplies...I have no affiation with sumo other than I have taken motorhomes to the factory and done R&D with them...my sons do installs at their shop... and some times I help with sudgestions...
 
kevin said:
My first question is what is that video talking about how maintance  on a air bag system is so high, and they have so many problems? The ones on my MH have required nothing more than a inspection, and the ones on my 3500 the same? If installed right and used right where is the big problem?

my second question if you stack 2 300lb springs on top of one another and apply 300lbs to them do they compress 1inch each? so a total of 2"?
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you are correct... and if you only compress the springs 1" it only takes 150lbs... since springs are measured at 1" compession...you have a 150 lb spring..

I've had cars where the person complained about harsh bucking car..they had one 300 lb spring... 300-16... I said... take the 16'' 300 out and put two 8'' 300lbs spring...NO way they shout.. it'll just get stiffer...wow they say after I do it....
 
But we are keeping the existing spring so that is a constant.  Guess your example is not sinking in. Or are you saying we should maybe look at it as the Sumo is just shifting the load curve of the leaf spring so we are not encountering the 3"=1200lbs range as quickly and keeping it maybe in the 2"=600lb range longer?  For that reason, we will not encounter that higher resistance as quickly and thus equate that to a smoother ride or am I still missing the point?

I will re-read your previous response when I get back for a fresh look and maybe it will sink in.  Thanks for being patient.  Just do not want to have high expectations with no ROI.   
 
Gregg said:
But we are keeping the existing spring so that is a constant.  Guess your example is not sinking in. Or are you saying we should maybe look at it as the Sumo is just shifting the load curve of the leaf spring so we are not encountering the 3"=1200lbs range as quickly and keeping it maybe in the 2"=600lb range longer?  For that reason, we will not encounter that higher resistance as quickly and thus equate that to a smoother ride or am I still missing the point?

I will re-read your previous response when I get back for a fresh look and maybe it will sink in.  Thanks for being patient.  Just do not want to have high expectations with no ROI. 
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to bad you are not in vegas...we could just put a set on and you could see the difference...pretty sure if you are not delighted with the results you could just return them  (sumo's)... never had that happen... but it could i guess  .. the other thing with sumos  doing a track or sway bar mod is not needed....but that has been my experience..... call tiffin... they pput them on at the factory
 
Guess I do not need to know how they work, only that they work and worth the investment.  Have only read a couple of people who did not like them after they were added and minor compared to the number of positive feedback.
 
MYRV2 said:
to bad you are not in vegas...we could just put a set on and you could see the difference...pretty sure if you are not delighted with the results you could just return them  (sumo's)... never had that happen... but it could i guess  .. the other thing with sumos  doing a track or sway bar mod is not needed....but that has been my experience..... call tiffin... they pput them on at the factory
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Man do I hope you, and many of the other posters on this product, are right in your recommendations.  Just ordered a set for the front.
 
Gregg said:
Man do I hope you, and many of the other posters on this product, are right in your recommendations.  Just ordered a set for the front and will see and post back.
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Ernie n Tara said:
Sorry! The correct answer is 600 lb./In. (a as I recall). Your description of the series spring operation is correct  but the deflection of two 300 lb./in. springs in paralled is 0.5 inches under a 300 lb. load or 600 lb./in.

The fact that your springs are progressive increases the deflection but it will still be less than an inch.

Ernie
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Read an article that if you are attempting to determine if springs are parallel or in series simply place a solid object in-place of one spring.  If that action eliminates all spring action within the suspension, the springs are in parallel.  Based on that, the SumoSprings are in parallel because you would have a direct connection from the frame to the axle.  Thus Ernie would be right.  Correct?

Whatever the answer, I hope that the SumoSprings can do their magic because ordered a set from eTrailer.  Great group of people to deal with and they price matched so think I got a pretty good deal from a company I have done business with in the past.
 
Wanted to update the information provided.  Installed my SumoSpring Max's on the front.  Some have posted that they only installed on the fronts and stopped there.  It raised the front about 1" which was not acceptable for me long term.  Ordered the rears to hopefully even things back out.  Installation of the fronts was easy.  Actually made it harder than it had to be only because it seemed too easy if that makes sense.  I did run into a situation where the mounting plate, on the passenger side, would not sit flush because of an existing washer.  A little grinding resolved the issue.  The driver's side just cleared.  Picture attached.   

Results in MHO: Some of the harshness was taken out of the ride.  Nothing spectacular, but definitely an improvement.  Seemed to reduce the rattling inside the coach.  They definitely reduced body roll when going around corners. Ordered the rear springs to hopefully level the coach back out and any additional improvement will be a plus.  Small disclaimer: I still have the Bilsteins OEM shocks on my unit because the unit had very low miles on it when purchased.  Some postings that I have read state that OEM shocks cause some of the harshness in ride.
 

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Finally finished my installation of SumoSprings Maxims and aftermarket Bilsteins.  Body roll seems to be much better and overall ride has improved significantly.  IMHO and on my particular RV, it was worth the expense. :)
 
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