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RV Q&A: Stray Power Wire

Originally Published in Trailer Life Magazine

Red letter Q
I bought a newer trailer and swapped out the batteries. I want to wire them in parallel, as I had done in my old trailer. But this trailer has a blue wire (with a 30-amp inline fuse), a red wire (with a 30-amp inline fuse) and a white wire (grounded to the frame). I believe the red goes to the positive terminal and the white goes to the negative terminal on the other battery. Where does the blue wire go?

Jay Monroe | via email

Green letter A
Since the blue wire has a fuse, it’s likely a power wire for some accessory, Jay, and it should be connected to the place on the batteries where you connect the main red power line for the trailer. The fact that the blue line has its own fuse indicates that it powers something without going through the RV’s fuse panel. It could easily be the power line for the electric A-frame jack, for example, and using an inline fuse for an accessory right next to the battery makes more sense than running the wires longer distances through the fuse panel. By tracing the blue wire, you can determine what it powers.

Safe Half-Ton Fifth-Wheel Towing

Red letter Q
I read your response to Bryan Pollock’s “Half-Ton Fifth-Wheel Towing” letter in the August RV Clinic, where it was suggested that some light trucks hauling fifth-wheels are probably overloaded, and I became alarmed that I might be part of that crowd.

I drive a 2015 Ford F-150 4×2 Crew Cab with the 3.5-liter EcoBoost engine, a 3.55:1 rear-axle ratio and the heavy-duty towing package. It has a maximum gross combined weight rating (gcwr) of 17,000 pounds and an 11,900-pound maximum loaded trailer weight rating. I pull a 36½-foot 2016 Highland Ridge Open Range Light LF295FBH that has double bunks and a gross vehicle weight rating (gvwr) of 10,995 pounds.

I happened to be leaving on a two-week camping trip when I read the letter, so I had the truck and RV fully loaded, including firewood, ice chest, chairs, games, and a full pantry and fridge. The fresh- and wastewater tanks were empty.

I weighed it at the nearby Flying J Certified Automated Truck scale (just $13 for two weights), and the loaded truck and trailer came in at 15,700 pounds, or 1,300 pounds less than the gcwr. Just the trailer axles on the scale came in at 8,580 pounds, or 1,820 pounds less than the trailer’s gross axle weight rating (gawr). The trailer alone, with its landing legs and axles on the scale but keeping the truck’s rear axle off the scale, came in at 10,120 pounds, or 875 pounds below the trailer’s gvwr.

I am happy to report that I am not among the group of overloaded light trucks hauling fifth-wheels. Thank you for teaching me how to determine this, as discussed in your reply to Richard Roper’s question, “Truck and Trailer Weight,” also in the August RV Clinic.

Isaac Andrade | Benbrook, Texas

Green letter A
Thank you for the detailed breakdown on checking out your truck and trailer weights, ratings, capacities and so forth, Isaac. You did it the right way with the lash-up loaded for a trip and ready to roll. To add one factor, it looks like your trailer’s hitch weight was about 1,540 pounds, after deducting its 8,580-pound axle weight from the 10,120-pound overall weight. You should check your truck’s rear-axle gawr, compare it to the rear-axle weight and see if your F-150 has adequate capacity to handle that trailer-hitch weight. You should be OK, but it wouldn’t hurt to verify the figures.

This is the kind of procedure that would help a variety of our readers
determine how their rigs shape up.

We appreciate your note, and congratulations on a safe and successful pairing.

Routine Roof Maintenance

Red letter Q
We now own our fourth fifth-wheel trailer since beginning our RV experience in 1997. Roof maintenance has never been a concern because we bought a new fifth-wheel about every five years. We’ve had our current 2011 Keystone Laredo 266RL for about six years now. Should we be concerned with roof maintenance? If so, what kind and how often? We do not have the luxury of storing the trailer under a roof.

Ron and Sue Seese | Medical Lake, Washington

Green letter A
Roof maintenance consists of washing, inspecting and resealing on a regular basis, Ron and Sue. Your owner’s manual will include specific cleaning and treatment recommendations for your Laredo’s rubber roof.
A regular maintenance regimen is needed to prevent chalking, black streaks and cracking. This usually consists of sweeping and hosing off the roof, scrubbing with a rubber-roof cleaner, then using a protectant product designed specifically for rubber roofs. Camco, Protect All and others offer suitable products, or you can do an online search for “RV rubber roof cleaner.”
Always confirm that the roof is walk-on capable to prevent damage and use extreme caution when you’re up on a wet roof. When in doubt, hire a reputable RV-detailing company to do the job for you. You should also keep a close eye on the fiberglass endcaps and keep those especially clean and well protected with a UV-resistant wax and sealer.
Because you can’t store your trailer under cover, the best thing to do is to use an RV cover that is sized and fitted to your trailer. Choose a good-quality product and install it as directed, and you’ll limit sun and weather exposure and wear and tear on the trailer. Another option for long-term durability (and low maintenance) is one of the permanent RV-roof treatments, such as RV Armor, that is applied over the roof surface and offers a lifetime material and labor warranty.

Boondocking Batteries II

Red letter Q
In response to Harold Harris’ letter, “Boondocking Batteries,” in August’s RV Clinic, I wanted to share my story. I recently added a solar system to my 26-foot Forest River Rockwood 2608SS travel trailer. I added a single 265-watt solar panel, a Morningstar ProStar MPPT charge controller with multistage charging (the one used for off-grid installations) and a TriMetric TM-2030-RV monitor that shows the exact input and draw on the batteries, which the charge controller does not. I added two 6-volt Trojan T-105 RE batteries rated at 225 amp hours each, which are more amp hours than golf-cart batteries.
Recently, we camped for four days on just solar with careful monitoring. My cousin is a solar retailer, and he set me up with an “industrial-grade” solar package. We are headed to Montana for a month or so off the grid, and I wanted to be sure that we get as much power as possible. We have a Honda 2,000-watt generator as backup, but that silence of solar is golden.

Robert Lauzon | Flagstaff, Arizona

Green letter A
Robert, it sounds as if you’ve put together a functional system that covers your needs. Yes, indeed, it’s nice to be able to leave the generator shut down most of the time. Choosing a charge controller that includes electrical-flow history is a good way to help monitor your system and how it’s doing at any point in the charging or discharging cycle.

Jeff JohnstonRV DIYRV Tech

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