Replacement Bearing Kit for a 2010 Harmony 21FBS

Updated 08/25/2025 | Published 08/18/2025

Question:

I have a 2010 Harmony 21 FBS Aluminum Superstructure AX5 by SunnyBrook. Dual axle. Trailer is 3800 pounds. Looking for new wheel bearings. Any help on correct bearing size would be appreciated

asked by: Gary W

Expert Reply:

Hey Gary,

What I'm seeing is that your 2010 Harmony 21FBS will have 3,500 lb axles so you need the Hub Bearing Kit # BK2-100. I wasn't able to find anything definitive about this though, so I do recommend checking the sticker in the middle of one of your axles to verify that weight rating, and be sure to let me know if it's something else.

Your trailer has a unique weight rating which is why I wasn't able to find something concrete.

Have you replaced bearings before, or do you plan on having a shop do it for you?

expert reply by: Jon G

Gary W.

8/24/2025

The sticker states: GAWR: 3500 lbs Mfg Date: 7/31/09 I have not replace d bearings before but plan to do it myself. I do a lot of work on my own cars. Any tips would be appreciated.

Jon G.

8/25/2025

@GaryW Glad to hear the axle rating matches what I mentioned! I'm linking an in-depth video that our installer team shot that has some great tips - my own personal tip would be to take your time. I tend to get into projects like this and just want to get it done (which isn't a bad thing), but then when I hurry, I tend to make mistakes. Take it easy, and you'll be just fine!

Helpful Links

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