What is Wrong with My Trailer Suspension? Why Have I Changed my Bearings 5 Times in 8 Months?  

Question:

Expert Reply:

Hello Dalton,

First off, thanks for the detailed write-up. No need to apologize, it's clear you've put a ton of time into this and you're dealing with a frustrating situation that honestly shouldn't be happening with a brand-new trailer. From what you described, it sounds like the root of your issues goes back to the trailer’s suspension geometry being off from the start.

That bouncing or “one-wheel-at-a-time” hop around 35 mph really does sound like a harmonic issue, and likely the result of misaligned spring hangers and a suspension system that can't move freely. You mentioned that the hangers were originally bent inward or outward, and even after straightening them, you still had to pry the springs into place. That alone tells me something isn’t right. Your measured spacing, 74 1/4” front, 74 1/2” rear, and axle seats at 73 7/8” is way outside normal tolerances. In most cases, you’d want spring hanger spacing to be within about 1/16" of the axle spring seat centers. The misalignment you're dealing with is definitely enough to put serious strain on the suspension, tires, and bearings.

Speaking of bearings, wow replacing them 5 times is not normal. Combined with the spindle wear and heat spots you mentioned, it sounds like your spindles are toast. That wear you measured (1.25–1.28” where it should be 1.375”) is significant and likely means the bearings were spinning on the spindle instead of riding properly. Once that happens, the axle needs to be replaced, there’s no good fix for worn bearing seats like that.

All of this, the odd bounce, destroyed bearings, damaged tires, and fight to reassemble everything points to the trailer's suspension mounts being mispositioned from the factory. That misalignment forces the springs and shackles into constant tension, which prevents the suspension from doing its job and transfers all that stress to your axle, hubs, and wheels. And yes, to answer your question directly: having the mounts too far apart definitely adds strain. You’re basically pulling everything outward when you assemble it, and it’s not designed to work under that kind of forced alignment.

It’s completely understandable to feel like lighting the whole thing on fire as this should’ve never made it off the dealer lot in this condition. If it were my trailer, I would go back to where I bought it from. If that is not a possibility I am happy to get you the parts you need for a need for a new set-up. Let me know how you would like to proceed. I also attached a great help article that goes over trailer suspension.

expert reply by: Kate F

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Single Axle Suspension
(click to enlarge)

Dalton B.

4/8/2025

Thank you so much for the detailed and very insightful response. I am contacting the dealer one more time and will go from there.

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Kate F.

4/8/2025

@DaltonB Good luck Dalton! I hope the company you bought it from attempts to correct the situation =)

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Dalton B.

4/14/2025

Update: Manufacturer and dealer both state that all of this is by design. Hard to shake that slimy feeling off but at least I know where not to trailer shop now. Thank you again

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Kate F.

4/14/2025

@DaltonB I am very sorry to hear that. I really wish they had better regulations to follow when it comes to building and selling trailers.

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