Recommended SumoSprings Trailer Helper Springs for Underslung Axles
Updated 07/13/2026 | Published 07/09/2026
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Question:
Looking for the right sumu spring for my rv 30 feet long tandem axles underslung leaf springs dry weight 5100 pounds loaded guess 6500 pounds what type would I need Thank you
asked by: Carson H
Expert Reply:
Hey Carson. The correct SumoSpring kit for your trailer is going to depend on the capacity of your axles. Since your axles are mounted in an underslung orientation there are two options that I have listed below:
3,000 lbs - 5,000 lbs Capacity Axle - SumoSprings Trailer Helper Springs w/ Line Relocation Bracket item # TSS-106-40
Please note that this kit requires 6" - 8-5/8" of clearance between the top of the spring pack and the bottom of your trailer's frame.
5,000 lbs - 8,000 lbs Capacity Axle - SumoSprings Trailer Helper Springs w/ Line Relocation Bracket item # SS33HR
This kit requires 7-7/16" - 8-5/8" of clearance between the top of the spring pack and the bottom of your trailer's frame.
The SumoSprings trailer helper springs are sold per axle. You'll need one set for each axle.
What capacity axles does your trailer have?
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Product Page this Question was Asked From
SumoSprings Trailer Helper Springs w/ Line Relocation Bracket - Single Axle - 3K to 5K - Underslung
- Trailer Suspension Parts
- Leaf Spring Enhancement System
- Boat Trailer
- Camper
- Car Hauler
- Snowmobile Trailer
- Utility Trailer
- 3000 lbs
- 4000 lbs
- 5000 lbs
- Single Axle
- SuperSprings Intl
more information >
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