SumoSprings anyone?

[Sportsdad60]

Another happy Sumo spring customer here. Caught a cross wind 25mph in Texas coming home in the spring to MT and I didn't even feel the cross wind. Wife asked when she saw the grass in the fields blowing, it was only then when I realized there was a cross wind! The Dually and trailer didn't know!

[Blackwellbp]

@MN-Mark

The sumo install was extremely easy. The most difficult/time consuming part was setting up the jack by each wheel to lift off the frame. Once you know the space between the frame and spring plate, setting up the sumo's takes just a few minutes. Then lift from the frame to let the suspension drop a half inch or so. Slide the sumos in, tighten the base nut/bolt, centre the sumo and hand tighten as much as you can. Start to finish for me was about two hours. I did not have to move any propane lines on my 2021 303RLS...sooo....you will not either.

I'm curious about your sumo springs. I also have a new to me 2019 2500rl and just took it on its first trip. 600 miles round trip. I noticed I am getting significant tire rub on the plywood floor and the clearance from tire to floor is about an inch less on the passenger side. Were you getting any tire rub and if so, did this correct that issue? From what I've seen, this model seems to have under sized axles from the factory.

[Hoopy Frood]

Check the condition of the springs first, make sure there is a good arch. My guess would be that they are shot, and look more like a "W".

[Blackwellbp]

Check the condition of the springs first, make sure there is a good arch. My guess would be that they are shot, and look more like a "W".

They do still arch upwards. I also just noticed I am getting excessive to severe to severe inner tire wear on all tires. The back driver side is almost smooth already. I'm sure the springs are likely worn out though. Did yours ever have tire rub?

[Hoopy Frood]

Never seen any tire rub, and there is a lot of room between the tires and the anyplace they can rub. If yours are that far down, and the springs are in good shape, I'd be looking around for other issues. Might check to see if there are two bolt holes in the spring hangers and/or equalizer hangers. Are the springs mounted on top of the axles or under? If on top, maybe you need a spacer to open things up a bit. This is just if your springs aren't shot. Pictures would be great.

You also might check your axles for camber. If your axles have flattened out then the tires will wear on the inside of the tire more than the center, due to the tires being tilted.

FWIW, you also might get the information off the axles and find out the specs on the axles, and springs.

[powerscol]

They do still arch upwards. I also just noticed I am getting excessive to severe to severe inner tire wear on all tires. The back driver side is almost smooth already. I'm sure the springs are likely worn out though. Did yours ever have tire rub?

I suspect you have bent axles - assuming the are either 3500 or 4400 Dexter that are what are called LT Tube. The are very easy to bend, especially when kacked on the axle. I bent 2 4400 on my 5th wheel during my Alaska trip (rough roads). The camber should go through the spring perch U-bolts - mine bent at the first u bolt.

Find a good spring/axle shop or heavy equipment trailer dealer and the should easily identify the problem. Most RV dealers don have a clue how to check.

Now if they are bent folks will tell you they can bend them back - don't . They will just bend again. Axles are relative cheep and easy to replace. Get new and go one size up on the axles and springs too. Get the STD wall not the LT wall.

Please post back on what you find out. If you bought it used and it had new tires, I think the seller pulled a fast one on you.

Good luck

BTW - If you let folks know where your from I am sure folks will help with places to go. If near Denver Iron Bear can help https://ironbeartrailer.com/trailer-axles/ Excellant customer service. I special ordered my replacement axles through them and they shipped to me.

[Flip94ta]

If you Google search bent 2500RL axles my own unit will be the top results and lead you to this site.

Your axles are most likely sagged or bent and the springs are tired. Both are a very common issue for 2019 2500RLs. As someone else posted they used a 3500lb axle but it was a thin wall light duty version. I suspect my replacement units are the thicker walled ones because they have held up nicely.

As for the springs, I think it’s touchy, if there’s only one inch now I would replace axles and springs…

GD/Dexter replaced my axles, springs and brakes free under warranty just after my warranty had expired. I had taken several picks while under warranty showing negative camber and tire wear but didn’t make a claim until a big two week trip had ended. Shout out to them for taking care of me.

With my new springs I could fit my fist between tire and floor. After five months in storage I had already lost an inch so now I was down to about 3-3.5”. I added the sumosprings and I still have that 3.5” or so. And it rides great.

If I were you I would call dexter or eltrailer and get prices on full replacement units, it’s the easiest way to do the job.

[Scott'n'Wendy]

I'm curious about your sumo springs. I also have a new to me 2019 2500rl and just took it on its first trip. 600 miles round trip. I noticed I am getting significant tire rub on the plywood floor and the clearance from tire to floor is about an inch less on the passenger side. Were you getting any tire rub and if so, did this correct that issue? From what I've seen, this model seems to have under sized axles from the factory.

I didn't have any tire rub to begin with, but the sumos aren't meant to lift the trailer. You only pre-load them about 1/2". They might reduce rub just a little bit? If you already have tire(s) rubbing the floor I would first check to see if the previous owner put larger tires on it then move onto checking leaf springs

[Blackwellbp]

I'm thinking I have sagging leaf springs and bent axles. I did some more research and did find you previous thread and read the whole thing. From what I'm seeing, my trailer came with 3500# axles with a 2 3/8 diameter tube. In 2019 they supposedly upgraded to 3500# axles with a 3in diameter tube. A year or so after that it seems they went to the 4400# axles. I guess I am unlucky and my trailer was build in early 2019 and was equipped with the 2 3/8 diameter axles. I know the axles are still under warranty but the rest of the coach is not. Problem is I am not the original owner so I have low expectations. I am sending over the pictures to the claims department now.

This is my second GD and the first was a 2018 2970rl that we lived in and put thousands of miles on without a single issue. Warranty or not, this is clearly a design flaw and it is shameful that GD has not issued a recall on it. Even on the sticker it says the gvwr is 7,495# but right under that it shows the axles are 3500#.. So it came from the factory over rated by 500#. Unbelievable and so unexpected from such a reputable brand.

I tried to attach a link to some pictures. I'm having a hard time figuring out how to upload pictures to this site.

https://photos.app.goo.gl/uk2L1EVZCZr4cdF27

[Hoopy Frood]

FWIW, they often figure the weight carried by the axles as the GVWR minus the tongue/hitch weight. Which would put your trailer within specs, but not by much. I agree Grand Design does many good things but adequate suspension does not appear to be on that list.