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LVJJJ's avatar
LVJJJ
Explorer
Jul 18, 2014

Old brakes, Old trailer

I have a 1985 Wilderness 3000CL TT, it is in very good condition, aluminum siding still shines, upholstery perfect, everything looks and works good, except the brakes.

I think it spent most of it's life sitting at an RV park near the ocean here in Western Washington as there is a lot of surface rust on the undercarriage, nothing serious. It seems to have been towed so little that it may be that the brakes are the original as well as are the bearings. Bearings are good and the shoes only half gone and drums are still good.

The brake springs and mechanisms on each wheel were rusted and stuck and therefore didn't work very well. Wires going to each wheel were in pretty bad shape and some not even connected.

I cleaned the mechanism off with brake cleaner and a brush, lubed the star wheels and got them to work like they should. Had to replace one of the magnets. Also fixed all the wires going to the magnets.

I've never been totally happy with the trailer brakes as they don't grab as much as they should. No way will they lock up. I can use the manual control (Prodigy) to slow things down but it takes a lot of pressure on the brake pedal to get everything stopped. I know that the manual control isn't supposed to be used to stop the whole rig, but on other TT's I've had, the manual control had a lot more effect. I like to manually engage the TT brakes first since the old van brakes aren't the best, but if I have to, a lot of foot pressure will bring everything to a pretty quick stop.

A couple of times on our last trip last week, the Prodigy briefly showed the trouble code "n.c." so the trailer brakes stopped working for a few seconds.

I should note that the tow vehicle is a 1965 Chevy Van with a 292 I6 engine. Been towing with it since 1988 and about a half dozen different trailers.. The trailer wiring from the Prodigy back is all new. When the brakes are applied the brake terminal (blue) registers 12v.

Today I jacked up the TT, hooked it up to the TV, took off all the wheels and gently applied the van brakes. All of the magnets were buzzing. When I rotated the right side brake drums there was some resistance and could hear the magnets contact the drums. However, on the left side, the wheel with the new magnet actually locked up and the rear wheel spun with no resistance or magnet contact (but the magnet was still buzzing). What's weird is that the trailer has always slowed down in a straight line and the brakes have never locked up.

The lever the magnet is connected to is real tight on the rear left side wheel, but the lever on the front one with the new magnet has a half inch of play before it begins expanding the shoes.

I've always done most brake and bearing work myself, but this one stumps me. Any ideas?

19 Replies

  • Yes. this 10 Gauge wire is thicker than needed. 12 gauge will probably work. But for a few pennies more (and 10 gauge wire has more outer sheathing protection), "up sizing" to thicker 10 gauge wire is worth it. Especially if you plan to keep your RV/TT for many years.

    Also remember that with inertia brake controllers (like Prodigy Px models), one should be driving > 20 MPH to test the trailer brakes. Having trailer hub on jack / block and apply TV's brake peddle won't activate its internal inertia trigger. In other words, TT brake hub won't often activate.
  • Wow!, great advice by everyone. Interestingly enough, I've been thinking I should run individual wires from the front junction box to each wheel, now I know I should. Didn't know it was called Star. I'm surprised that 10 gage is recommended, that's a lot more power going to each wheel than I thought I'd need. My question is, since the wires attached to the magnets aren't 10 gage, wouldn't that be overkill?

    The stock wiring was absolutely tiny, maybe 20 to 18 gage going from one side to the other, thru the rusty axle. I replaced it, but not with 10 gage.

    At least I did seal all my new connections with liquid black tape.

    I'm impressed with the wire protection many of you have employed, that makes a lot of sense. On all of my dozen new trailers I've ever owned, I've noticed that the brake wire connections were hanging loose, all over the place. That's always concerned me, but I stupidly figured the manufacturer knew what he was doing, not. I at least cable tied them up under the frame rails.

    Any idea why when applying a small amount of brake pedal voltage (Prodigy shows 1.6) would cause one wheel to lock up and the other not to work at all? Could bad wiring to that?

    Just saw reply from opnspaces. I do run the Prodigy at B3 and at full gain. I keep the brakes adjusted as tight as possible. There is a dedicated ground wire going from the van to the TT. I don't rely on the trailer ball for a ground. In fact, doing this recent testing, the van isn't even hitched to the TT, its just close enuff to plug in. From what everyone has said, my current TT brake wiring system clearly sucks.

    I've always used the manual control when stopping. The van brakes, while in good shape, aren't all that strong (all drums). I like the trailer to pull back on the van, so I gently manually apply the brakes to help scrub off speed long before I need to stop. When you drive a flat front forward control van you drive way ahead of yourself and must ready to begin applying the brakes way before you think you might need em.
  • I would start with adjusting the brakes again. I've adjusted mine before and they loosened up after a few miles. In reality I imagine the brakes seated into their normal running position. I never had to adjust a third time though.

    Next I would go with the star wiring. Mine is still the factory wiring, but some day I will convert to star as it just seems like it would be better.

    Also you mentioned leading with the trailer brakes and a Prodigy controller. Are you using the manual lever to lead with the trailer brakes or cranking up the boost. If using the lever, try maxing the boost and you might not have to touch the lever again.

    If you are getting an intermittent NC reading I would check your ground. You should have a dedicated ground wire from the trailer back to the tow vehicle. Do not rely on aground through just the trailer ball.

    True story, I had a motorcycle trailer with a 4 blade flat wire connector, but the ground wire was not connected to the plug. I pulled the trailer that way for years (teenager) without a known problem. Then one day I was turning a corner at dusk and the trailer hopped a bit through the gutter and I saw the lights all go out and come back on. It took me a second to realize that the coupler had enough slop that as the trailer bounced, the coupler lifted slightly off the ball breaking the ground connection. I added the ground wire to the plug and the problem never occurred again.

    to sum my suggestions up:
    Set Prodigy to boost level 3. (manual is online or call them for one)
    Increase gain on Prodigy.
    Adjust brakes again.
    Check, repair, or replace all brake and coupler grounds.
    Rewire in star pattern and include grounds into this rewire.
  • Please ignore me if you don't feel this is helpful. Your tow vehicle is ... antiquated. To approach modern safety levels you need great trailer brakes. If it was me (and I know it is not), I'd buy new brake assemblies with drums and bearings. Then I'd run new wires from the new assemblies all the way to the 7 way. The cycle of bad wiring, bad magnets, bad grounds, and rusty parts needs to be cut off at the pass.

    Now, some advice you might use. The controller behavior and the brake operation you described indicates bad wiring. The some oxidization that rusted all that stuff probably oxidized the wiring too. It starts at the connections and spreads down the copper turning it black.
  • .

    For all my trailers (RV, utility, boat), I rip out (remove) the factory linear wiring design and replace with STAR design. Solder All connectors, cover the mar connector, and cover with liquid rubber. ALL brake wire runs("control wire" and its ground wire) are separate 10 Gauge thickness and all wiring inside plastic PVC/PEX piping and/or plastic wire loom. Thus, triple protection from road junk / road salt. Before and After upgrade with STAR design is like night and day comparison. And best of all, the electrical flow is now balanced.

    For a few pictures, surf:
    - click here for factory design -
    - click here for STAR design -
    - click here for wire support at wheel hub -
    - click here for PEX tubing -
    - click here for PVC junction box -

    If wondering, all my trailers get STAR wire design using thicker 10 gauge wiring to each wheel hub. Without hesitation. And, all my customer bought trailers get STAR wiring design as well.

    For such an old trailer and knowing Brakes is #1 safety, I would replace with new Brake Assembles and brake hubs on each wheel hub. Thus, "NEW" parts - instead of trying to sand / wash old rusty parts.

    If wondering, trailer tires should NEVER lock up on normal driving conditions. If they did, fish tail skidding (especially on wet / ice roads) is at extreme risk. The trailer should "dramatically" slow the attached Tow Vehicle but RV/TT tires should never lock up.

    If using a Time technology Brake Controller, immediately rip out, trash it, and replace with motion sensor / inertia technology brake controller. Prodigy P2 or P3 are best electric Brake Controller to use.

    Hope this helps.
  • Sounds like your whole brake system needs to be refreshed.

    After sitting for 20 years accumulating rust and corrosion I doubt that cleaning them is not going to restore the springs to fully operational levels. The retainer pins are probably weaken and could break causing a catastrophic failure.

    I imagine that your TV is close to it's max towing capacity and still has drum brakes, so you need all the trailer brakes you can get.

    If it was my TT I would do a complete brake job with all new parts, from the backing plates out.
  • Considering the rusted chassis, are all the brake grounds good? It sounds like you have a good understanding of the wiring and mechanical issues. I had a brake destroy itself once in the mountains of Utah and had to remove the whole assembly roadside. We traveled to the Phoenix area with 3 brakes and never felt a pull to one side.
  • Two things to deal with, the electrical part and the mechanical.
    If the wires were original to the brake locations, are they wired in a star configuration or are the primary brake wires daisy chained from one to another. The star type is superior, IMO. 12 on the Prodigy should be enough to move all the magnets to the drums. IIRC, my Prodigy II shows 4 or so during regular braking. I don't use the boost function. I don't know if measuring current when the wheels are up will turn up a malfunctioning brake but it may turn up a difference in that one bad location. If it was the same as others, that might eliminate the electrical side as a potential issue.

    If the drums aren't worn to a large degree and the shoes have adequate pad that isn't glazed, maybe adjusting them tighter may improve the braking. FWIW, I adjust mine until they are lightly scuffing and even a little resistance, at times. It depends on the age of it all and what the condition is of the contact area. Another alternative is to replace the shoes, they are still rather cheap.

    AFAIK, the lever with the magnet should have very little resistance. Maybe you have one that is caught up?
  • I had to replace the brake magnets on my pop-up's wheels. They looked good but there was no continuity when the second one failed.

    Even with new magnets there is no way those 7" brake drums will lock up the camper wheels.

    I do not know how many TT brakes will lock up once they have a few miles on them.