Parts Needed to Add Disc Brakes to 2018 Keystone Montana 3121RL
Updated 09/22/2025 | Published 09/18/2025 >
Question:
I have a 2018 Montana 3121RL and am considering adding disk brakes. It has Dexter 7000lb axles, 1877496 not sure if that is the part number, I have a picture of the axle label but dont know how to attach. Which system brand do you recommend? Can you determine the bearing size from the axle label?
asked by: Larry O
Expert Reply:
Hey Larry, since your 2018 Montana 3121RL has 7k tandem axles the DeeMaxx brake kit part # DE66AR that you referenced would be the kit you'd need to add disc brakes to your trailer that includes everything. DeeMaxx makes really nice disc brake components and their actuator is really rock solid so you'll be really happy with this. This actually comes with the needed bearings as well so you don't need to look that up or source them separately.
Product Page this Question was Asked From
DeeMaxx Disc Brake Kit w/ Actuator for Tandem Axle Trailers - 13" Hub/Rotor - 8 on 6-1/2 - 7K
- Trailer Brakes
- Disc Brakes
- Marine Grade
- 8 on 6-1/2 Inch
- Hub and Rotor
- 1/2 Inch Studs
- 7000 lbs Axle
- 15 Inch Wheel
- 16 Inch Wheel
- 16-1/2 Inch Wheel
- 17 Inch Wheel
- 17-1/2 Inch Wheel
- DeeMaxx
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Larry O.
9/19/2025
Thanks Jameson! I really like your Irish whiskey.