View Full Version : Trailer Actuator clunk

06-09-2009, 04:35 PM
I read through other posts and didn't come across this, but from what I've read online, a slight clunking sound from the trailer/actuator when you accelerate from a stopped position is normal. Mine does it stopping and accelerating, but it really feels like more than a little clunk. It's actually a pretty loud clunk. I'm going to bleed the lines, etc. soon, but just curious if anyone knows if this clunk really is normal.

06-09-2009, 05:00 PM
I think you might be on the right track checking the fluid and bleeding the lines. I had a trailer with surge brakes that would do that because there was no brake fluid in it.

06-09-2009, 05:07 PM
I think what your hearing is a good clunk. The level to which the system actuates is how abrupt the stop is and the condition of the actuator mechanism with the moving parts.

06-09-2009, 06:35 PM
I never hear a clunk when i hit the breaks. I hear some squeaking from my trailer breaks and that bothers me, i hate squeaky breaks. When i pull away from a stop there is a clunk or a thud, pulling sensation on the hitch and i know this is the breaks releasing. I generally do this, light turns green, light gas on the truck till i hear that clunk and pull sensation, then i step into the gas on the truck to accelerate up to speed. I try to minimize how fast i start out so this pulling doesn't cause any undue wear or stress.

06-09-2009, 07:37 PM
Mike you will hear the clunk soon, trust me! I have a bit of it now too, it's the nature of the beast. What your hearing & feeling is the shock inside the actuator moving back and forth as well as the internal slide. I had the same issue with my old trailer which had the UFP A-60. Mine was real bad though so i replaced it and it resolved it until it wore in. I've had these things apart more than i care to relive. You WILL know when it's worn out. Btw, bleeding the brakes does not get rid of it.

06-09-2009, 11:08 PM
Check for play in your reciever. One of mine has a little play and it makes a lot of noise. The other one is tight and there is only a little noise.

06-09-2009, 11:47 PM
Well when you brake you compress the slide in on the trailer and apply force to the master cylinder causing the disc brakes to be applied (and shorten the tongue). Now when you accelerate you are pulling the slide out until it hits the limit of its travel so you (tow vehicle) are actually getting a small head start on the boat and trailer and since it is probably metal on metal you are going to hear a noise. This is the nature of the system. The Moomba isn't too bad but my big 25 offshore boat really makes a CLUNK!!!! The first couple of times I towed the boat I thought I was ripping the truck or trailer apart. But in this case I am trying to move more mass with this beast (6600lbs)! I have thought about making some urethane bumpers for it but just haven't done it yet.