Info Needed to Pick Out Replacement Actuator and Surge Drum Brake Setup on Trailer

Updated 09/15/2025 | Published 05/25/2025

Question:

I am replacing the complete surge brake system on an old flatbed trailer. It has an Atwood actuator, but everything will be replaced. I dont know the weight rating of the axles. Brakes on only one axle this trailer carries light weight rowing shells. Do I just go by the old drum diameter and shoe width to pick the loaded backing plates? It wont be backed into water. How do I pick a new actuator? Tongue width, ball size, what else? Well get steel brake tubing and hose at the local auto parts store. Thank you

asked by: Ken S

Expert Reply:

Hey Ken, you'd want to start with determining the axle capacities so that all of the parts can be matched. But are you doing new hub/drums too? The diameter and depth of the hubs is helpful but it doesn't tell the full story. Axle capacity, wheel bolt pattern, and do you have a manual or electric reverse lock out currently.

For an actuator the Demco part # DM72VR would work great as it fits same size trailer frame as what you have now. We have brake lines too like the Kodiak tandem axle brake line kit part # 20TA-BLKIT.

expert reply by: Jameson C

Jameson C.

9/12/2025

Hey Ken, did you find the axle capacities to help with matching all the parts for your trailer? I'm curious to know how the Demco actuator and the other components worked out for your setup. Your experience could really help others working on similar projects!

Ken

9/12/2025

@JamesonC On the old trailer that I put the new brake system on, I used the dimensions of the old drums and shoes. I matched those old dimensions to the new parts. The new brake system is working very well.