Axles, shocks and Sumo Springs Questions

[dlowrey]

I have a 2022 Montana 3231CK. Road Armor blue shackle between the axles.
The axles are rated at 7k each, the GVW of the fifth wheel is about 16.5k. I understand that about 2.5k is carried by the pin box to the truck.

The trailer seems to me to be awfully close to the axles max rating. I am concerned about momentary high loading caused by road bumps and bounces. I have seen videos where trailer springs flatten out or factory shackles fail. For the moment, I don't want the expense of independent suspension.

This is my first experience with a 5th wheel. As a younger person working on my hot rods, I would have favored shocks over any kind of helper springs on a car. That said, the Sumo Springs blue look attractive. Also e-Trailer offers a 4 shock kit.

Your thoughts would be appreciated.

Thank you.
-DL

[Carl n Susan]

Have you weighed the RV and truck to accurately determine the pin weight and axle loads? I bet your pin weight is closer to 3,400 lbs.

[dlowrey]

Probably true. Not CAT scaled, but it is on my to do list.

[AZ Traveler]

Donald,

Before adding aftermarket suspension recommend you weigh the rig configured as you travel. If you are over GVW find a way to lighten up. If you are well under GVW you will know you have reserve capacity. I am not against adding aftermarket solutions but having good data will help you determine where you are.

Focus on regular suspension maintenance including greasing wet bolts and checking torque on fasteners. Also include daily visual inspection on the road.

Many of us have run our rigs for years without breakdowns with regular maintenance that discovered issues before a breakdown.

Tight turns while backing or forward that get you close to 90 degrees put extra stress on the suspension. The roads you travel will also have an impact.

[dlowrey]

Yes, I agree, regular maintenance and inspection is important. My concern is that the suspension appears to be close to max load from the factory. The impact of potholes, the poor condition of some interstate road, etc. is more likely to overload the suspension and break something. If I can do something now to mitigate these impacts, I may avoid broken springs and shackles later. So that is why I am thinking shocks absorbers or Sumo Springs or some other mitigation.

[rvman]

I have had the Sumo Trailer Springs on my rig for the last 8500 miles of travels. Noticed a definite improvement in ride. Less body roll in corners and in heavy cross winds. Less chucking on our quality interstates. Each sumo adds 500lbs of carrying capacity at 65% compression. My thinking was exactly like yours. Really felt like the factory should have put 8000lb axles on the 40 footers. My feeling is the Sumos keep the springs from "wrapping" when you hit that inevitable pothole or bridge transition. I do carry an extra spring and a few wet bolts as extra insurance. Also added the shackle brace kits from Mor-ryde to strengthen the frame to shackle connections.

[Djgrimaldi]

As info, our trailer (3121) has a gvwr of 16,000 pounds. We have two 7,000 pound axles for a combined weight rating of 14,000 pounds. When taken to the CAT scale the weight on the rear two axles is 12,060 pounds. The rest of the weight is distributed to the truck at the King Pin.

[LeftOverParts]

We have the same model but 2021. Although the axles are rated 7K each, they are probably the heavy wall model. You also probably have 7 leaf, leaf springs which are rated for 4K each. Any doubt you can contact a Dexter dealer and send the axle sticker info and leaf count, and ask them to verify. (That’s how I found out). With your 2022, you probably also have the benefit of having v-clips on your spring hangers.

As others have said, best to weigh your trailer. With almost empty tanks, ours has a 3100 pin weight and about 13.5K with basic traveling/camping gear. Not saying a big bump or huge pothole won’t cause problems but you’re probably not as close to the limit that you think you are.

[Djgrimaldi]

You are absolutely correct. Our 2022 comes with the V-Clips. Shackle Holders are welded to the trailer frame also braced everywhere needed. The Axles are the Dexter Gladiators which are beefed up. So Happy we purchased this unit over all others. As I hear of other complaints about shoddy builds I get a smile on my face when I compare theirs to ours.