What Disc Brake Kit Is Recommended For 2021 Grand Design Momentum 397Th
Updated 09/02/2025 | Published 08/09/2025
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Question:
I have a 2021 Grand Design Momentum 397Th. Which Disk Brake kit would you recommend?
asked by: Michael C
Expert Reply:
Hello Michael, thanks for reaching out. We should have the parts you need, and the DeeMaxx Disc Brake Kit # DE26AR may work for you, but there is no way for me to look up your camper online to know exactly what disc brake kit will fit. RV manufacturers just aren't that specific with their online literature.
Based on your GVWR I am assuming your have three 7,000 lb rated axles, but if you could check your axle sticker and confirm this that would be great. The 7K axles use a standard bolt pattern and bearing combination so as long as you can confirm that you can be sure the # DE26AR kit will work for you. It uses the # 25580 inner bearing and # 02475 outer bearing which are standard. The hubs are 8 on 6-1/2" bolt pattern with 9/16" studs. You will want to confirm the stud size for your wheels and make sure this matches. 7K axles should be 9/16" but please confirm.
This kit comes with everything needed to convert the triple axle trailer over to EOH disc brakes. The only other thing you would need is an EOH compatible brake controller in your truck. Most aftermarket controllers are compatible, like the Tekonsha P3 # 90195. Some factory controllers may not be compatible though.
Do you already have a brake controller? What kind?
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Product Page this Question was Asked From
DeeMaxx Disc Brake Kit w/ Actuator for Triple Axle Trailers - 9/16" Studs - 8 on 6-1/2 - 7K
- Trailer Brakes
- Disc Brakes
- Marine Grade
- 8 on 6-1/2 Inch
- Hub and Rotor
- 9/16 Inch Studs
- 7000 lbs Axle
- 16 Inch Wheel
- DeeMaxx
more information >
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on Trailer Brakes
Jesse M.
9/2/2025
Hey Michael, did you have a chance to check your axle sticker and confirm the details for the disc brake kit? If you’re still looking for a solution, I’m happy to help.