One Wheel on a Boat Trailer Locks Up and Trailer Actuator is Leaking Brake Fluid

Updated 11/21/2011 | Published 11/19/2011

Question:

I have a 2007 Ventura single axle bunk trailer model VB 3000 with hydraulic surge brakes. After storing the trailer for the summer I found both wheels frozen. One freed up immeadiately, the other did not until the boat was on it and being towed out of the water...dont ask how I got the trailer to the boat ramp! I just moved the trailer with the boat on it and the same wheel was frozen. It did start to turn after being rocked back and forth. I plan on jacking up the trailer with the boat on and take off the tire and wheel hub to inspect. I have watched your informative videos. The hydraulic resevoir does not stay filled yet I have been unable to find leaking hydraulic fluid anywhere.I have filled it a couple of times over the last few years. If it has been leaking inside the hub is it best to replace the entire hub and if so what part do I order? BTW the wheels are by Loadstar, the brakes hubs and actuator are by Tie Down. Thanks

asked by: Rob B

Expert Reply:

It sounds like you have a leak in the system either in a brake line or at the actual wheel cylinder. If this is the case, you may not have to replace the entire hub or brake assembly, just the part that is leaking. A leak can also draw air into the system and cause the brakes to lock. My theory is that it is the wheel cylinder on that one side.

After you inspect the brakes and find the culprit, make sure that you bleed the braking system. There are vacuum type systems that you can use to bleed the brakes but you can also do it the old fashioned way. Our installer covers this method in the video linked for reference.

If your trailer has disc brakes, then there will not be a wheel cylinder. However, the seal for the piston in the caliper could have dry rotted and may be leaking.

expert reply by: Michael H