Leaderboard

BRIEF UPDATE July 14, 2026: I accepted the generous offer by John @jd1923 and Chris to come farther west to Prescott and tackle this 'Check Trailer Wiring' issue. While my Oliver was jacked up, I was able to take care of some other regular maintenance work, and John helped out with that as well, but I will focus here on the trailer wiring. The main job was to replace the brake wires beginning at the left side (below the battery box) where the wiring exits the hull, and connecting new wires to each of the four brakes. John suggested pulling the new wires through the axle by taping them to the end of the old wires, for various reasons, but once the taped joint reached the opposite side and I needed to pull it out through that small hole in the axle, the tape broke apart. I tried pulling the new wire through that hole with some needle-nose pliers but the wire was so soft that small pieces were breaking off. So we reverted to my initial plan (based on several others here on the forum), and ran the new wires along the rear side of the axles, using split loom and zip ties to anchor it. We found that the butt connectors I ordered from Amazon did not hold; John tested one and the wires pulled right out without any effort. He had some older style butt connectors that we used, with much thicker metal inside, and then we added tape on the connections. I will probably come back to those taped joints with some liquid tape to try to weatherproof them better. (I saw that someone had used a clear sealant -- if anyone knows what that is called, I would like to find it. The liquid tape I have is black like tar.) The finished job looks really good. Note that I haven't tested by towing yet. After the rewiring, I measured the amperage at each wheel, after disconnecting the 7-pin connector from the truck and pulling the Emergency Brake pin. Each one measured about 3.0, with the left front measuring slightly higher. This was a good result in so far as the power was flowing from the Emergency Brake battery (I believe on the Oliver, this is the trailer battery; SOB trailers have a separate little battery for this power). After the tires were back on and everything was back in place, I tested again using the power from the truck through the 7pin connector, with John's son Adam helping me by being at the controls in the truck. Measuring the two main wires exiting the hull (below the battery box) the amperage was 1.85 and 1.71 on the left front and rear wires. This measurement is obviously without being in motion, and my understanding is that the truck will not provide the full power to the brakes in this case; I'm not sure what amount should be expected here, but power is flowing to both wires from the truck. Quoting from @Geronimo John in an older forum post, "... modern brake controllers sense when a vehicle is stopped and back off the power flow to the magnetic coils when stopped..." Yesterday, John and I performed another set of tests on the 7pin Cable wires where they enter the hull and exit the cable, inside a double sized junction box behind the small panel below the vanity sink (see earlier photos in this thread.) We tested amperage for each of the wires, and the 7pin cable seems to be working fine -- even jiggling the wire at the connector and below the Oliver -- so we elected not to replace it. Of course, once again, this is not in motion driving down the highway. None of this is definitive until I actually tow the Oliver, tomorrow morning. I will report again in a few days, and try to add some photos here for clarity. I don't think this is resolved yet, but making progress on eliminating things is good. Many heartfelt thanks to John, Chris and Adam -- they have all been extremely gracious hosts and very helpful, and have cheered me up as well. Many thanks as well to all the other forum members who have been helping out with ideas and links and questions. Now we are heading out for some fun!