Looking To Replace My Attwood Master Cylinder 85736
Updated 12/09/2025 | Published 11/16/2025
Question:
I need help finding a replacement parts on my 2001 Chapparal boat trailer brakes. Original part Number: ATWOOD85736
asked by: Aaron L
Expert Reply:
Hey Aaron,
Unfortunately that master cylinder from Attwood is no longer made and cannot be replaced. For that you would need to replace the whole actuator. The closest replacement we carry for that is going to be the Demco # DM72VR brake actuator. This is a bolt on actuator for 3" wide trailer tongues and offers a 7,000lb towing capacity. Hardware is not included but it uses 2-1/2" x 4-1/2" Grade-5 bolts which you can source locally from any hardware store.
What kind of boat do you have?
Product Page this Question was Asked From
Demco Hydraulic Brake Actuator - Drum - Zinc - 2" Ball - 7,000 lbs
- Brake Actuator
- Surge Brake Actuator
- Farm Trailer
- Boat Trailer
- Construction Trailer
- Travel Trailer
- Utility Trailer
- Bolt-On
- 7000 lbs GTW
- 2 Inch Ball Coupler
- 3 Inch Channel Tongue
- Drum Brakes
- No Lockout
- Demco
more information >
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Nick S.
12/8/2025
Hey Aaron, how did the Demco brake actuator work out as a replacement for your Chaparral trailer? Your update could make it easier for others trying to replace that old Attwood setup.