Sumos Were Worth It

[Chance]

Originally Posted by penguin

As Jamie said they do a lot more than just address sag.

You're correct, they do. In fairness to the point made by blw2 (that they are primarily a helper spring), the description given by JamieGeek is consistent with stiffer springs which is a common configuration for helper springs.

Simply replacing springs with heavier/stiffer springs (or installing multiple springs in combination to do the same, as in Sumos) would also reduce mushy ride, reduce lean on turns, and would also lift front end some if replaced with comparable-length OEM coils.

Originally Posted by JamieGeek

I found that it tightened up the front for me. The Axis no longer seems as mushy in the front and doesn't lean near as much in turns as it used to.

That Sumos often replace OEM bump stops for convinience and ease of installation seems to muddy their role somewhat. As shown in posted pictures they are essentially a helper spring to make suspension stiffer. It's not that different than small air bags that also replace bump stops; except that they are not adjustable. They may also provide a small amount of damping which steel coil springs or air springs don't to any significant amount.

[penguin]

Originally Posted by schreinertms

What is the difference in the color of the Sumo springs? Some model numbers show up in black or blue. If that a significance? And then there are yellow ones?

The blue ones are the lighter weight 106-40's (500lbs). The black ones are 106-47's (1000lbs). I think yellow is for the rear. Per sumo literature the blue ones are for a van (lighter weight) and the black for a box truck. I would say the blacks are better suited for the Axis/Vegas as they are very heavy.

[Joe-FL]

Originally Posted by greenfield3

I am not inclined to install them on my 37KT, What is a reasonable price to have them installed? My dealer is quoteing $1k.

For the heavier F53 chassis (front and rear) I paid around $1,130 on line to get them. I was thinking of installing them. After reading instructions for my coach and finding out how many holes had to be drilled plus needing a jack big enough to raise the rear axle, I decided to have a shop install. The RV shop that installed them had never done a set, they had only done air bags. They charged me just under $800.

Total = Just under $1,950

[Joe-FL]

Originally Posted by vkb

Ron is happy with our Sumos Front and Rear. We will give then another test next week...heading to Colorado. Winds of western KS & east Colo will not be such a challenge with them.

We now have just over 1,600 miles on the Sumos and my observations are:
* at first the ride seemed a little harsh but they now feel "broken" in.
* on calm days it is like driving your car down the interstate.
* in 20mph plus cross winds you feel much more stable and in control.
* no noticeable lean when making slow tight turns.

Even though we generally only do around 300 to 350 miles a day, I am confident by the way the coach handles now that I could easily do a 600 mile day if needed.

[TyCreek]

I posted pictures of height measurements before and after Sumo install ... measured again after an hour or so of driving around town and the result shows it settled back to within 1/8" of the before measurement. This is good news in a way because there should be no need for another alignment Initial in town observations are that the Sumo's did eliminate the harshness of bump stop impacts. Hitting the highway and into the wind now ...

[upnyfolks]

I installed the front 106-40 sumos that I purchased on Ebay for $100, we have since completed a 6500 mile trip in our Axis and I found that they significantly reduced the jolting in the front end when hitting bumps.
The front Sumos, an alignment, and front and rear heavy duty anti-sway bars have our Axis handling very comfortably.

[TyCreek]

Well ... after a couple days of driving on many familiar surfaces with the HD/1000lb Sumo bump stops mounted. I noticed no negative behaviors! Most noted improvement is smoother handling of surface transitions and less rolly polly on patched, uneven, frost heaved roads. Fairly easy comparison because our rig with only a trackbar added, over 2yrs ago now, has had no other chassis mods.

We departed on the freeway into erratic headwinds much like most of our departures where we take the freeway. I could feel and hear the wind hitting the coach from an ever changing direction. My impression was that of slightly less effort needed to stay in lane at around 75mph with wind and vehicles passing at 80+ ... though effort/attention was still needed ... partly because 75 is a bit too fast in those conditions. Quite noticeably less effort and reduced floaty feel on the rough two lane road surfaces we traveled. On the way back we had of course the typical wind conditions where a very comfortable 71mph was "guess/estimate" netting a mph or two more in a relaxed cruising speed (very subjective to conditions e.g. not positive yet, though no complaint). I've driven this route many times in similar, higher and lower wind conditions so I do have decades of driving various RVs on the same roads. But most importantly have continuous input from a very sensitive passenger

My takeaway is; don't be afraid of the HD (1000lb) bump stops if you are front heavy on the E chassis! Pretty cheap and simple to install. Eliminating the bump stop impact is a good experience, for sure on rougher surfaces and I noticed no increased harshness on the smoother road surfaces.

Here's a picture of last night's sunset from our camp chairs ...

[TyCreek]

When I took the measurement where I previously mentioned that it settled down to near original height, it was based on measuring the nearest side (R). Didn't think much of it and expected things to settle down from the fresh off the jacks measurement (middle in the pic clips) as I didn't figure there would be much lift. Just assumed the other side would be the same e.g. didn't give it much thought.

Anyway, I got to thinking about the considerably lower left side so I measured and it looks like the Sumo's are pushing up to the tune of about 1/4". That side had noticeably less space between the bump stop and therefor higher compression so Sumo's progressive spring rate must be working full time to net 1/4" lift at rest (carried weight). I even put the slide out to make sure that measurement matched whatever position it was in when I took the first picture before the Sumo install.

[Long & Winding road]

Im refreshing this old post..... What do you guys think about the Sumo's now??

I dont want anything Harsh.... Was the 500# worth it? Still feels about right to you? What about you guys with the 1000 # Sumos? Too harsh, Just right?

Are these Sumos softening up with use?

What about your ride height? Same as stock over time? Still a little higher than normal?

Im been thinking about Sumos lately for the front of my 2017 Axis. I like what was said about removing the harshness of the OEM bump stops. Plus the help with sway control/body roll.

I installed the HD Front sway and a Rear track arm along with Saftey Plus stabilizer... So the old girl handles pretty well IMO.... But Im always looking for improvment.... even if its a small improvment.

I just turned 10K mile on my RV so everything looks like New when I check it out every few months.

[paulwadley]

I put Sumos on the front and rear of my 2018 Thor Siesta 24SS class C. They work great. It help to eliminate the sudden sway when ever I get passed by a larger truck. They also helped out when entering and exiting parking lot driveways. They were easy to self install.

Paul

[Lt Keefer]

With the sumos on the front only of my Hurricane the ride is definitely better. A drive across the windy panhandle of Texas no longer wears me out. The expansion joints on the highway are also less noticeable.

[Long & Winding road]

Well im trying to get more details on which one to go with for my Axis. Did you go with the 500# or 1000# sumo's?

Im leaning towards the lighter 500# since I have my HD front Anti -Swaybar and Rear track arm.

Also Like to hear from JamieGeek and TyCreek since they posted a few years ago. Opinions change over time.

[Lt Keefer]

I went with the SSF-170-40-2 on my F-53 chassis. They have a 3000 lb capacity according to the internet.

[Pete'sMH]

I put them on the front of my 18.000 GVWR F53 and felt that the change was minimal. DW said she couldn’t tell the difference at all. Certainly wasn’t worth $500 to me and I’m not putting them on my new coach. CHF and Roadmaster steering damper is all I’m doing. Just my experience.

[vkb]

Originally Posted by Long & Winding road

Im refreshing this old post..... What do you guys think about the Sumo's now??


I just turned 10K mile on my RV so everything looks like New when I check it out every few months.

Good morning ! having looked back at the beginning of this post, I see we responded in 2017....having just installed the Sumos front and rear on our 24.1.
Reminding those of you who are not familiar with them...they DO replace the bump stops. When installing the Sumos, Ron noticed immediately that the Sumo does not allow for any wiggle room ...where the bump stop had an inch or so before it engaged.
Ron still likes the install of the Sumos...no regrets.

With that said....WE ARE SOOOOO LOOKING FORWARD tp getting away from home. Our local riverfront campground which is small anyway...has limited sites available...offering every other site...
My THOUGHTS ON THIS IS...campers are probably the best example of folks social distancing....when we visit around the campfire, etc...we don't elbow to elbow ...we drag our camp chairs around where we can visit with everyone in the group....we invented social distancing !!

with that said....WEAR YOUR MASKS....STAY SAFE....AND ENJOY LIFE as much as you can !!

[TyCreek]

Originally Posted by Long & Winding road

Well im trying to get more details on which one to go with for my Axis. Did you go with the 500# or 1000# sumo's?

Im leaning towards the lighter 500# since I have my HD front Anti -Swaybar and Rear track arm.

Also Like to hear from JamieGeek and TyCreek since they posted a few years ago. Opinions change over time.

Sumo's are soft, sort of squishy, so don't fear leaning toward higher spring rate. My long term experience with Sumo's on the Axis front, ended with RV change. Have them on the rear of my pickup now to reduce loaded squat and they have minimal unloaded ride impact. No change noticed in either case during the time I had them.

[jannnda]

I added to the front only. Didn’t tell the wife. The next trip when we were on the freeway she asked me what I did. She noticed that passing trucks were not felt and the ride was better. Still not great, but better. I added to the 18000 F53. She now wants me to add the rear.

[Rysiek]

Originally Posted by jannnda

I added to the front only. Didn’t tell the wife. The next trip when we were on the freeway she asked me what I did. She noticed that passing trucks were not felt and the ride was better. Still not great, but better. I added to the 18000 F53. She now wants me to add the rear.

Just installed SumoSprings front and rear on 2015 Axis 24.1 yesterday. I went with SSF 106-40 (500lb) for the front and SSR 106-47 (1500lb) for the rear axle. I used my 20T bottle jack to lift the coach at 4 corners. Started with the front driver side as suggested by manufacturer. I thought that removing the wheel (which I did on that side only) will speed up the process but that was not necessary. The front of passenger side as well as the both rear side were done without wheel removal. Front is really easy to do as long you use 10mm long socket. The rear procedure is the same except you have to deal with brake line bracket (on the driver side) which uses the same bolt. On the rear passenger side the exhaust is right where the SumoSpring is going. No drilling required. Just pretty simple bump stop replacements. It took me longer to move around heavy jack, safely set it up and lift the coach by hand then to replace the bumps with SS.
Today, I drove the coach for about 20 miles and could tell the difference right away. Still soft ride (that is why I went with softer springs) but without any swaying, rocking from side to side. Very solid, car like drive. We had a very strong winds today but the coach was not affected by those at all. I drove entire 20 mile route using only one hand. Incredible. It was almost like driving my SUV. I am very happy with the results. After the installation, the height of the coach have increased by 1/2 inch. The only negative thing I have noticed is that the motorhome was slightly pulled to the right. Maybe this was caused by gusty winds? I think, I might need to get wheel alignment done. Will test this again. Can't wait to go on a longer trip.

[Ron1Z]

Installed the Sumos on the front of my Windsport and a rear stablizer on the back, made a world of differance in the ride.