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Replacement Master Cylinder for Demco Actuators - Disc Brakes

Replacement Master Cylinder for Demco Actuators - Disc Brakes

Item # 5672
Our Price: $65.08
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Shipping Weight: 1.15 lbs
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5672 - Disc Brakes Demco Brake Actuator
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Replaces the master cylinder for your Demco actuating brake coupler for disc brakes. 1-833-496-1390 to order Demco accessories and parts part number 5672 or order online at Free expert support on all Demco products. Great prices and Fastest Shipping for Replacement Master Cylinder for Demco Actuators - Disc Brakes. Accessories and Parts reviews from real customers.
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  • Reviews (19)
  • Q & A (0)
  • Videos (1)
  • Photos
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Demco Accessories and Parts - 5672

  • Brake Actuator
  • Master Cylinder Parts
  • Master Cylinder
  • Demco
  • Disc Brakes

Replaces the master cylinder for your Demco actuating brake coupler for disc brakes.


  • Fits Demco actuating couplers for disc brakes only
  • Bolt holes dimensions: 2" x 3"
  • Overall dimensions: 2-3/4" x 4"
  • Made in the USA

5672 Demco Replacement Master Cylinder - Disc Brakes

Video of Replacement Master Cylinder for Demco Actuators - Disc Brakes

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.

Video Transcript for Review of Demco Brake Actuator - Replacement Master Cylinder - 5672

Jeff: Hello, everybody. This is Jeff at Today we're going to take a look at the replacement master cylinder for the Demco disc brake actuators. This is designed to fit the Demco brake actuators for disc brakes only and the reason is this master cylinder is designed to operate a brake pressure of 1500 PSI, which is the pressure for disc brakes. This will not work with drum brakes because it operates in the lower 1000 PSI pressure.Now this part does include everything shown here on the table. The composite master cylinder, the composite lid with the cork gasket, four mounting bolts that you put in there with washers to install it and then this automotive style diaphragm cap that screws in.

Now a few measurements on this, the bolt hole dimensions. In other words, these bolt holes right here. The measurement center to center. Three inches this way, two inches that way.And the overall dimension of the cylinder itself. Is four inches, like two and three quarter inches, but again when you do put this together, make sure your gasket gets on there.

Line it up there you have your four holes. Just use those to screw it down and then put your cap right on there. If you notice there is a sticker on this cap that says, "Do not use the fill plate if your outer case is threaded." So just a warning to pay attention to that sticker, but that should do it for the review on the replacement master cylinder for the Demco disc brake actuators.

Customer Satisfaction Score:

Customer Reviews

Replacement Master Cylinder for Demco Actuators - Disc Brakes - 5672

Average Customer Rating:  4.7 out of 5 stars   (19 Customer Reviews)

Replaces the master cylinder for your Demco actuating brake coupler for disc brakes.


I’ve ordered from etrailer several times! It’s always delivered fast, packaged nicely, and reasonably priced. From brakes, bearings, to my recent master cylinder purchase. They have the parts to keep our trailer reliable for our cross-Country boating trips.


The new master cylinder is not cast iron like the original so it will never rust or pit up and the reverse solenoid was a breeze to drill and tap in. Justin W. from e trailer set me up with the perfect replacement. I’m one happy boater!


It is an exact fit, I tried to get the master cylinder from the company that made the trailer tongue and was told they don’t make them anymore, I was very happy To see this one bolt right in


Replaced the original DEMCO 5672 MC for a coupler assy that was 2 years old. Hope this one lasts longer.


Good Product. Was back ordered but they kept me informed and up to date via email. ETrailer is a great company to do business with.


I received my master cylinder in just a few days. This was a direct replacement and it all fit. I did watch a few of your videos and they were very helpful.


I swapped it out with the drum one and worked fine. Now I have disc brakes on my trailer


This replacement master cylinder was the exact fit. Just what I was looking for.


Exact part I needed at a very reasonable price!!


Came with everything needed, fit as original and restored braking.




Great product. Just as advertised and shipping was very fast. Thanks!


Great service, Will buy from again. Fast delivery.


Fast shipping and correct product for the job great communication.


Ships super fast! Great product.





See what our Experts say about this Demco Accessories and Parts

  • Replacement Master Cylinder For A 2016 Demco AT6000P Car Hauler
    Yes, the Replacement Master Cylinder for Demco Actuators # 5672 will work fine with your 2016 Demco AT6000P car hauler since it utilizes a Demco actuator. Additionally, this master cylinder is made in the United States and has an overall measurement of 2-3/4" wide and 4" long.
    view full answer...
  • Can Demco Replacement Master Cylinder for Hydraulic Disc Brakes be Used with Drum Brakes
    Hydraulic drum brakes operate at around 1,000 psi where disc brakes are higher at about 1,500 psi. So the maser cylinder for disc brakes, part # 5672, is not the same as what you need. Instead you need the master cylinder for drum brakes, part # 5650.
    view full answer...
  • Are There Replacement Master Cylinders Available for Brake Actuators
    Yes, there are replacement master cylinders for surge brake actuators like the Demco Actuator part # DM8203102 that you referenced. If this was the actuator that you have you would want the Replacement Master Cylinder # 5672. If you have a different actuator I attached a page that has all of the replacement master cylinders we offer.
    view full answer...
  • Can Surge Coupler/Actuators Be Converted from Drum to Disc Brake Operation
    Surge couplers for drum and disk brakes use different master cylinders that operate at different pressures, lower for drums and higher for discs. It is possible to swap out the master cylinder in a surge coupler to convert it from one type of operation to the other. Depending on the number of brake assemblies, trailer length, etc, larger brake lines are sometimes also called for with disc systems. It sounds like you have free-backing drum brakes like # 40715 on the trailer now, which allow...
    view full answer...
  • Replacement Brake Actuating Coupler for Upgrade to Disc Brakes
    The bolt hole dimensions of the Demco Brake Actuator # DM8669112 are 12-1/2 inches on center and 3 inches on center. I've attached a photo to assist. The Titan # T4747220 has mounting holes that are 3 inch on center so 2 of the 3 holes will align with your current coupler. Instead of changing out your entire coupler, you may want to simply change out your master cylinder on your Demco Actuator using the Replacement Master Cylinder for Demco Actuators - Disc Brakes # 5672. This will...
    view full answer...
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  • Will the Demco Brake Actuator # DM8202022 Work with Disc Brakes on a Boat Trailer
    The Demco Channel Only Trailer Actuator, part # DM8202022, was designed to be used with drum brake applications only. You could use this actuator with disc brakes, but you would have to replace the master cylinder in the actuator with the Demco disc brake master cylinder, part # 5672. To save yourself some time, work and money, I would recommend going with the Titan Adjustable-Channel Brake Actuator. Titan offers a bolt-on and weld-on version of this actuator. For the bolt-on actuator,...
    view full answer...

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Info for this part was:

Employee Jeff D
Installed by:
Jeff D
Employee Wilson B
Updated by:
Wilson B

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