Brakes lockup on on trailer when in reverse

[tpbadgers10]

Couldn't find any threads on this subject but I'm having problems with my 2013 shorelander trailer. When backing it up the wheels on the trailer lockup. It doesn't do this all the time just every now and then until today. How I get them to unlock is just put the truck in drive for a few feet and then try backing up again, usually just once does the trick. But today I had to try 3 or 4 times before it would back up and I was just about up against a fence and would not of been able to pull forward anymore. Its done this once when backing up into the garage and the other times when backing up into the unloading dock. Today they even locked up when the trailer was empty. And I was up against a curb so just kept on backing up and the wheels slid on the pavement. With a boat on the trailer it does not move. The trailer has only 200 miles on it and the first time this happened it only had about 50 miles. Wheel bearings are greased fine and are not dry. Anyone ever had this happen to them or what you may think the problem is? Let me know thanks.

 

[Creekwood]

That is how the hydraulic brakes work. When the truck brakes, the pressure of the trailer on the hitch pushes the hydraulic cylinder on the trailer tongue which applies the trailer brakes.

From shorelandrs web site:

The ShoreLand’r disc brake system is equipped with a five wire electrical harness and a “flat five” type plug-in. The additional wire (blue) must be connected to the tow vehicle’s back-up lights. This is necessary for the system to override the trailer brakes while backing. A five-wire pigtail for the tow vehicle is available as an accessory from ShoreLand’r or from your local auto parts store. If the electrical system override is not functioning, or in an emergency, the only way to back the trailer is to use the “lockout key” shipped with each trailer. The lockout key is a metal tab that is square on one end and round on the other. When this key is placed in the slot on the left side of the tongue, it will prevent the surge brake piston from moving, thus locking out the brakes. WARNING: IT IS VERY IMPORTANT TO REMOVE THE LOCKOUT KEY BEFORE TOWING THE TRAILER AS THAT DISABLES THE BRAKES.

 

[tpbadgers10]

Sorry for my ignorance but this is new to me. They may of locked because before I back the trailer into the water I unplug the power from the trailer to the truck. Is that causing the over ride thus locking the brakes? I don't see that lockout key that you are talking about but I will do more research on that.

 

[chuck1]

You may not have a lock out key. But correct about the extra wire. What I did on flat ramps made a wedge with a block of wood that I could fit to keep the surge brakes from engaging when backing up. On step wrap did not have to deal witj it because the weight of the boat was pulling down the ramp. Like you hated to have the trailer hooked up wjen putting it in the water.

 

[Lazy Daze]

Sorry for my ignorance but this is new to me. They may of locked because before I back the trailer into the water I unplug the power from the trailer to the truck. Is that causing the over ride thus locking the brakes? I don't see that lockout key that you are talking about but I will do more research on that.

Yes, unplugging will negate the ability of the trailer to automatically keep the brakes from locking up in reverse. This is because you have disc brakes. Drum brakes are different. The locking key would have initially been in either your owner's pack or directly attached to the stuff hanging on metal wires by your coupler. It's "L" shaped and will fit into that oblong slot on the side of the coupler.

Keep a magnet attached to your trailer and you can use that to keep the lockout key in the slot until you want to take it out.

"According the book", you should always unplug before backing into the water. I've launched so many different combinations of boats/trailers (in addition to my own boats) I can't keep count. The only time I disconnect is if something looks obviously wrong with the lights. I have NEVER had any issues due to leaving the lights plugged in. However, if you want to do that, wait until the trailer is starting to go downhill before unplugging.

 

[randmhall]

My dad always unplugged before dunking. That was before LED lights and sealed light fixtures. I haven't bought a pair of unsealed trailer lights in 20 years. Now all may lights are sealed LEDs. I never unplug.
And yes, the disk brakes need the 5th wire to back up.

 

[Bama Boater]

My dad always unplugged before dunking. That was before LED lights and sealed light fixtures. I haven't bought a pair of unsealed trailer lights in 20 years. Now all may lights are sealed LEDs. I never unplug.
And yes, the disk brakes need the 5th wire to back up.

I also have sealed LED(s) and never unplug until I disconnect the trailer back at the house. I remember once I wanted to reposition the boat so didn't bother plugging it in. The locked trailer brakes reminded me of the backup wire.

 

[NH Tooner]

Wire that blue wire to your backup lights

 

[Lazy Daze]

Wire that blue wire to your backup lights

That is already the way it is on his trailer/truck. He totally disconnected, hence the problem.