Probably pretty simple, but I don't know trailers.

2000 RoadRunner triple-axle, disc surge brakes:

Sometimes the trailer will NOT back up. It appears to be that the surge brakes are locking up upon engaging reverse in my truck ( 2004.5 Dodge Ram 2500 Cummins ).
This can present a problem when attempting to launch the boat, as most of us prefer to launch "boat first".

Any thoughts ?

This may occur because as you back the trailer, it assumes it's weight is actually shifting forward and engages the brakes. You should be able to place a piece of metal in in the gap in front of the surge plate on the neck of the trailer. It will keep it from sliding and engaging the brakes. Be sure to remove the metal before getting on the road. Hope that helps.

Jon

It does not appear to be an electrical problem.
I have now clamped a couple pieces of steel between the tongue pins and the neck of the trailer to keep the trailer from sliding. Seems to work proper now. . . I'll just be using the clamp for launching, not driving, until I can resolve the issue. There must be some kind of 'damper' to prevent the slide mechanism from engaging unnecessarily. This'll be good enough to get me in the water tomorrow for the SCOPE Poker Run . . . hopefully.

Tempest - I keep my boat on a lift in Huntington Harbour. Fountain 32 Fever. . . BTW, I am originally an Easterner, and I know damn well what a Midnight Express is. Always liked 'em.

See ya on the water.

Holy cow, glad your in CA and not in IL. If you hook up your electric correct you can throw away your steel and c clamps and baling wire and duct tape and trailer your boat like everybody else. If that don't work you can always launch the boat truck first.

Rouxsterre, do you have the round or flat electrical connection to your trailer? if flat, there isn't a third pin for release. my driveway is long and steep, I use c-clamp sometimes too.

These are surge brakes,not electric,right?Unless something new is out there(and it may be)it's ALL mechanical,no wires involved.

Also, I have had a problem if you stop hard then shift into reverse the solonoid locks out, but the brakes are already applied hard. After stopping try giving a little jerk forward then go into reverse. This will turn on the solonoid with no pressure on the master cyl. Worth a shot.

Not all disc surge brakes have the anti-backing selenoid. some use a little lever or pin beside the ball that has to move in an "L" shapped slot to lock out the surge brakes. The preasure has to be off the brakes, then you can move the lever or pin up in the slot. The brakes then will not lock up. If you move ahead first the pin will release and the brakes will work again. The trailer that I had with this type of backing system didn't have to be engaged at the ramp because at the ramp the trailer is pulling backward on your hitch. The only time I had to engage the backing lever was when I was backing into my shop.

I have had this problem numerous times since having disk brake setups. The C-Clamp method works ok if you are on level ground but I have found that it does not work very well on any kind of uphill grade or in gravel. I would like to take the Dico coupler apart and see if there is room for a pin so I would always have a mechanical lockout option. If anyone has successfully done this please let me know.

I had a problem like that a while back. In the back of the master cyl there is a bracket w/ 4 holes that 4 solid steel dowells travel through. One of the brackets were bent jamming the steel dowell not permitting the actuator to do it's thing.
Another thing you may check is the backup valve screwed into the back of the master as mentioned. A single wire comes out of the vavle. With the trl attached to the vehicle (ground), run a hot wire to that wire and listen for a click from the solenoid. If it dont click, change it.