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Jelisfc
11-18-2003, 19:05
I have an enclosed sled trailer with Dexter axles and electric brakes. Is there any adjustment to them? One of my left tires tends to lock up. I haven't changed my controller but the one tire must be braking harder. I put up with it this summer but I need to get it fixed before the roads get bad.

Inspector
11-18-2003, 19:28
Do both axels have brakes? How heavy is the trailer? Some light trailers have to much brake. Adjusting the brakes is the same as adjusting your car or trucks brakes with drums.
I usually adjust to just lock but not tight and back off the adjuster until I have slight drag while rotating the wheel.
Your brake controller may be porting to much power to the brakes. The newer electronic controllers can be adjusted to brake the trailer without locking up and still be effective.
Weight is the variable here. As I said you may have to much braking capability for your trailer.
Denny

tanker
11-19-2003, 02:32
You may have a short in the brake wiring. Do the wires go through the axle tube? That is cause for concern, as the wires will from bouncing up and down get a bare spot and ground out at times and not at other times, this will cause a wheel to lock up. I had this on my past trailer. I pulled the wire out of the axle tube, after exhausting everthing else, and found the wire worn bare. I ran a new 2-wire cable from left to right on the outside of the axle tube, and secured it with proper wire tie wraps. As Inspector mentioned above, brake adjustment is the same as any other drum brake procedure, adjust up until both brake shoes expand out to the drum, then back off until the wheel spins free.
First step would be to remove all your wheels and drums and take a look inside for any problems, good time to repack wheel bearings, and I always put a little white brake lube on the backing plate where the shoes make contact, and also disassemble the adjusting wheel to make sure they turn free. smile.gif

HowieE
11-19-2003, 05:11
If trailer brakes are allowed to wear down without periodic adjustment they will tend to lock. This is because of the mechanical method of application in electric braking systems. The swinging arm from the magnet increases its mechanical advantage as its radial movement is allowed to increases due to shoe wear, unlike hydrolic brakes were brake application pressure is a function of pedal pressure only.
While Dexter braker are not as pron to locking as Kelsey Hayes brakes are they still require periodic adjustment.

Jelisfc
11-21-2003, 11:40
Thanx for the direction. I need to crawl under there and see about wiring, adjustments, etc. My controller is the same one I've had since getting the trailer. It does have brakes on both axles and it weights 3500 empty and I haven't had more than 1000 lbs extra in it.

I need to double check but I think the brakes have acted up since installing my lift. I haven't gone to a dropped hitch but the trailer doesn't sit level. With a lot of brake and not much weight on the front axle that might be the problem.

Has anyone ever disconnected an axles worth? It may be illegal in MN I need to check. The trailer is rated to 7K but even with three sleds I'm only at 5000 to 5500.

HowieE
11-21-2003, 12:57
I don't think I would disconnect an axle. Trailer brakes are not so dependable that one can afford to give up 50% of the system.
I would level the trailer to the truck and pay attention to your controller settings.
One way to set the controller on trailer brakes is to roll at about 25 mph, with a normal load on the trailer, and hit the controller with the hand switch full on. If the brakes skid slack of on the controller till they just do not skid in this test. If your controller has a reasonable application rate this should be good.