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RV Clinic July 2015

Originally Published in Trailer Life Magazine

Towing in Reverse

Q: I have a 2005 Dodge Ram 3500 longbed 4×4 with a 5.9-liter diesel engine, a 48RE automatic transmission and single rear wheels. I tow a 33-foot fifth-wheel that weighs approximately 11,000 pounds loaded.

When I back up on level ground, it does fair. When I try to back up a 5 percent grade (the grade I have in my yard to garage my trailer) or steeper, I get a torque converter stall and a transmission fluid heat-up alarm. The local Dodge service department says this is normal. If this is a true statement, then maybe Trailer Life should test trucks (Ram, Ford, Chevy, etc.) in reverse on a grade also. If you cannot back up your RV, why have the truck?

Emil Zgabay, Adkins, Texas

A: A truck should be able to move its rated load in reverse, Emil, but many owners of these trucks have cited a torque converter that feels “too loose” (has too high of a stall speed for the application). BD Diesel Performance and other companies offer “tighter” torque converters that remedy this issue. You did not mention if your driveway is curved or not, but if it’s straight or slightly curved, you might consider backing up in 4WD low range, which will take advantage of torque multiplication and let you move the trailer into its spot very easily. — Jeff Johnston


Sparking Battery Source

Q: In February’s “Mystery Power Draw” RV Clinic letter, John Kester had questions about seeing and hearing a spark when he reconnects his battery lead. I had a 2008 Forest River Rockwood with the WFCO power converter. I discovered the converter has capacitors in the electronic circuit. These discharge over time when the battery is disconnected.

When John reconnects the battery lead, these capacitors draw a momentary current that causes the little spark he sees and hears. I found the same spark when I unplugged either of the two 40-amp fuses found in the top center of the fuse board. These are safety fuses that blow in case a battery is connected with reverse polarity.

My solution and recommendation to John and many other folks is to install a battery-disconnect switch. This will save the battery(s) from gradual discharge by those phantom loads found in all RVs.

Danny Dobson, Louisville, Kentucky

A: Installing a battery-disconnect switch is one of our standard answers for solving a battery-drain-in-storage problem. Thank you for sharing your note about the capacitors in the converter. — J.J.


Shaky Trailer Brakes

Q: I purchased a 2014 Shadow Cruiser 313BHS late last summer. I have found that the trailer brakes do not seem to have enough braking force. The tow vehicle is a 2013 Suburban 4WD half-ton with a factory brake controller. I checked the adjustment of the trailer brakes, and they drag slightly. With the wheel raised off the ground, the wheel stops rolling when the brakes are applied. However, the trailer can still be pulled forward at engine idle, even with the emergency brakeaway cable pulled. I suspect that either the wires are undersized or the brake shoes are saturated with grease. Any suggestions would be helpful.

Tim Sielaff, Forestville, Michigan

A: You’re right, Tim. Grease saturation can make the brakes ineffective. You can easily check to verify the grease theory by removing a wheel and drum to see if everything’s clean inside. Given that your trailer isn’t very old, I’d look elsewhere for the problem — and I’d start with the Suburban’s gain setting on the integrated brake control. Gain is the adjustment that regulates the maximum voltage that’s sent to the brakes, and it allows the user to adjust that voltage to accommodate trailers of different weights and different numbers of axles, and therefore, different numbers of brakes.

Check your owner’s manual and adjust the gain higher than it is currently set, then check your braking power again. With the truck and trailer rolling slowly, perhaps at 15 mph, you should be able to stop the truck and trailer with the manual-application brake lever. The trailer brakes shouldn’t lock up but just draw the combo to a stop. This may take some trial and error to find the right setting. If it doesn’t work with the gain set at 100 percent, move to the next step.

To check for wiring flaws, turn the gain all the way up and have a helper apply the manually activated emergency brake lever. In a process of elimination, use a multimeter to check the voltage in the power wire at the brake magnet. With the gain up, the voltage should be in excess of 12 volts. If not, check the main power line where it meets the axles and is distributed to the drums. Next, move to the front of the trailer and check the voltage at the plug. If you find good voltage, the problem lies “downstream” from that point, and you have something wrong in the wiring, either a faulty ground connection, bad power wiring with a faulty connection or some such defect. Inspect the wiring and you may well find your problem, which can then be repaired. — J.J.


Refrigerator Fans Revisited

Q: I have a 2013 Evergreen Bay Hill fifth-wheel with a double-door Norcold gas/electric refrigerator in the streetside slide. I read the two “Refrigerator Fans” letters in the April 2015 RV Clinic regarding refrigerator cooling fans. While I feel that the refrigerator works OK, the cabinets around it stay pretty warm. I removed the upper vent door to see if there was a fan, and to my surprise, two-thirds of the opening is covered by a piece of paneling. Is this normal, or should I remove it and install an aftermarket fan?

Don Frank, Phoenix, Arizona

A: If the vent opening is partly blocked by a type of wallboard or paneling due to some “misunderstanding” at the factory, that could cause a reduction in refrigerator performance. The fridge vent door opening has a specified square-inch dimension, per the fridge manufacturer, to provide a certain amount of airflow, and if that airflow is partially blocked, it’s going to harm performance. I’d start by talking to your dealer about the situation and see if you can get them to perform the modification to make it right. If you feel comfortable with such projects, be sure to check for wiring or plumbing behind the area you’ll be cutting.

Absorption refrigerator cooling fans are optional and not required to make the unit perform as it should. Some manufacturers install them at the factory because they designed the cabinetry or located the refrigerator in such a way that cooling airflow is not up to manufacturer’s specifications.
If the refrigerator works OK as is, you don’t need one, but it sure can’t hurt if you do choose to install one. — J.J.

Q: I read the “Refrigerator Fans” letters in April’s RV Clinic, and they caused me to again contemplate something I’ve often pondered. My RV’s fridge is on the totally exposed road side of my camper, and at many campsites it gets full sun for a good portion of the day. I’ve thought about making a fabric sun blocker, the same size as (or slightly larger than) the exterior fridge panel. I envision it being mounted about an inch (maybe 2) out from the wall and removed for travel. While blocking the direct sun, it would still fully allow air to flow through the panel’s vents.

Is this a good idea and would it be beneficial (or potentially harmful) to the efficiency of the refrigerator?

Michael P. Gleason, Bangor, Maine

A: Your idea sounds perfectly plausible. Absorption or compression, the cooler a refrigerator’s environment, the better it’s going to perform. A portable shade seems like a great way to help keep your fridge operating in top shape. As long as you leave enough space between the shade and the RV side wall for air circulation as you intend, it should be fine. — J.J.


Hitch-Weight Calculations

Q: When a manufacturer, specifically Forest River, determines the hitch weight of a trailer, are the propane cylinders installed and filled and a battery installed? The weight of these two items alone could add 100 pounds to the weight. Are those weights also taken into consideration when determining the gross weight of the trailer? The only thing documented on my Forest River trailer is the deduction of a full tank of freshwater from the cargo weight. Love your magazine for RV Clinic alone, but the rest is pretty darn fantastic as well.

Tom Poe, Finksburg, Maryland

A: Thank you for the kind words, Tom. Most trailer manufacturers measure the unit’s weight without the propane cylinders filled or battery aboard, just as they leave the freshwater tank empty, and in some cases, the weight also doesn’t include certain options they install. At best, a manufacturer’s posted weight figure is just a guideline or starting point when making your tow rig and trailer setup calculations.

If, for example, the trailer has a 6,000-pound gross vehicle weight rating (GVWR) and the manufacturer says it weighs 4,500 pounds dry and empty of cargo (leaving an alleged 1,500 pounds of payload capacity), you should add the full propane cylinders and battery weight to that base figure, as well as the freshwater weight. The hitch weight will definitely be boosted by the battery and LP-gas weight. Better yet, take the trailer to a certified scale to determine its actual weight, and you’ll know exactly where you stand. — J.J.


Empty or Full Water Tanks?

Q: My wife and I are fairly new to RVing. We recently traded in our 2014 Coachmen 27-foot motorhome for a 2015 Grand Design Solitude 37-foot fifth-wheel. A few days after the purchase, we were talking to one of the salesmen and were told that we should make sure all water tanks were empty when traveling or risk damage to the tanks. I asked what we should do if we were going dry camping. He said to try to find somewhere close to the campground to fill up. For some reason, this does not sound right. Is it safe to travel with water in the freshwater tank?

James Holliday, Sebring, Florida

A: Just when you think you’ve heard it all, something like this comes along. There is no danger to your freshwater tanks if you travel with them full or semi-full of fluids. That salesman could have been concerned that, with the fresh and waste tanks full or partly full, the trailer could be overloaded by exceeding its gross vehicle weight rating (GVWR), in the event it has a minimal cargo capacity in addition to its wet, loaded weight. You can check that by taking the trailer to a certified scale and weighing it, wet and fully loaded for the road, and comparing that figure to its GVWR. And use your fluid tanks on the road; that’s what they’re for. — J.J.


Summer RV Storage

Q: We are planning to leave our 2014 40-foot fifth-wheel in Apache Junction, Arizona, for the summer. What plans should we make to keep it from getting too hot? We have the wheels covered, but should we cover the two air conditioners? We plan to spray conditioner on the slideout seals and put the slides in. We will also put water containers inside so it will not get too dry. High temperatures can range from 100 to 115 degrees Fahrenheit here in the summer. Could you advise us about anything else we should do?

Dennis and Rosemary Howard, Buffalo, Missouri

A: You’re taking the right steps, and one more item would be to use a fitted RV cover on the trailer. A good quality RV cover will shade the trailer from direct sunlight and provide some small degree of insulation. The trailer will still get hot, of course, but the cover avoids having the skin, window and door seals, plastic A/C covers and the like exposed to direct sunlight. Be sure to leave roof vents and some windows open a bit to provide air circulation. That’s about the best you can do under the circumstances. — J.J.


RV Wind Resistance

Q: I have been a Trailer Life subscriber for about three years, and I have never seen an article about methods to reduce wind resistance on travel trailers. I just finished a trip from Kentucky to Arizona and back, and could not help noticing how much the 18-wheelers have been doing to reduce their wind resistance. They have rear fairing arrangements and even fairings under the body of the trailer.

There must be a way for us to capitalize on that research and add a fairing of some sort to our trucks that would help the air move more smoothly over our travel trailers, and even a way to attach some type of fairing on the rear of the travel trailer to disturb the vacuum area directly at the back. Even a 1 mpg improvement would pay dividends for me, as I anticipate an 11,000-mile trip to and from Alaska in 2016.

John Taylor, Lexington, Kentucky

A: Those aerodynamic enhancements you see on commercial trucks work, John, and many would also likely work on RVs such as travel trailers. It’s largely a matter of cost of the devices versus potential gains and payback in the form of improved mpg. An average over-the-road fleet truck may drive 120,000 miles per year, and according to a Freightliner engineering source, those aero devices can save an as much as 10 to 15 percent or more. Even a big truck that achieves only 4 or 5 mpg can rack up the savings over that type of annual driving mileage.

The average RV owner drives relatively few miles per year. Commercially built aerodynamic devices, such as a tail-end fairing for the trailer, the underside air dams or a fairing type of device for the back of the truck could be costly enough that the average RV user would recoup the money only after many years of trailer towing.

There are commercial wind wings available that can be mounted on a pickup cab when towing a fifth-wheel trailer or the back of a truck bed cap for those who tow a travel trailer. As per some wind-tunnel testing done by Ford some years ago, they work, but they need to be as large as practical and angled to direct the air back up and over the top front edge of the trailer. They also work best at freeway speeds, as that’s when wind drag starts to become a serious factor. You’ll need to run some numbers on your average towing mpg, think about your annual towing mileage and the cost of devices to determine if they are right for you. — J.J.


Black-Tank Dumping

Q: We have a 2013 30-foot fifth-wheel Keystone Montana Mountaineer. I have a hard time dumping the black-water waste tank, even when the trailer is level. The first few times it took more than an hour. I had to beat on the drainpipe to get it to drain. Then I found if I raised the front of the fifth-wheel 6 to 8 inches, it dumps much easier but causes extra wear on the landing gear. So I had a septic company send a camera through the line and tank. There were no clogs, but when the camera entered the tank, it dropped down, meaning the bottom of the tank is lower than the drain. I contacted the dealer where I purchased the fifth-wheel, and they said they had never had the problem. I tried to contact the manufacturer concerning my problem and got no response.

Homer Rhodaback, Waldport, Oregon

A: The drop-down discovered in your tank plumbing is odd, Homer, since most waste holding tanks are designed with a lowered area with the drain plumbing attached at the lowest point. The way such tanks are usually built into an RV makes replacement an expensive and complex process, although it can be done if absolutely needed. Many such tanks are large and flat to fit between the frame rails, and that doesn’t help the waste flow any. Rather than use your landing-gear jacks, you may choose to run the tow vehicle’s rear tires up on some leveling blocks to raise the trailer’s front end during dumping.

It sounds as if you didn’t have enough water in the tank in addition to the waste solids. That can cause slow or incomplete draining in even the best waste-tank plumbing setups. As a workaround, you can try adding freshwater to the tank until it’s nearly full, then dump it, and the extra volume of freshwater will help flush it clean.   — J.J.


Slideout Seals

Q: In the March RV Clinic letter “Slideouts…Don’t,” you gave Frank Guinan several tips on his RV’s slideout problem. One of those tips was to clean and lube the slideout seals. How do you clean the seals, and what lubricant would you use?

Tim Rodkey, Clearfield, Pennsylvania

A: The type of cleaner needed depends on what type of dirt is getting on the slide seals. If it’s just dust, a universal cleaning product would be sufficient, but if it’s tree sap, for example, you’ll need to get a stronger cleaner to remove the pitch. I’d start with Simple Green or another mild spray-on product, and, if needed, use something like Fantastik spray cleaner. For slideout seal lubrication, avoid any petroleum-based product. Protect All, Camco, 303 Aerospace and a number of other companies offer slideout care kits and sprays, which are available at Camping World and other sources. — Ken Freund


Disconnect Switch

Q: We own a 2014 travel trailer that has a battery-disconnect switch. When I pull the switch out, the battery is in use. Pushing it in disconnects it. My question is, do I keep the switch in when plugging it in at a campsite or at my home?

Tom Watson, Phoenix, Arizona

A: The battery acts to stabilize system voltage and absorb alternating current “ripples” that get through the power converter into the 12-volt DC system. This helps protect circuit boards and reduces hum in audio devices. Therefore, the battery should be connected when the RV is being used. You need to determine if you have a “smart” charger in the power converter or not. If it has a multistage charging regimen, then you can leave the battery connected when the coach is parked at home and plugged in. If not, then the battery should be disconnected and kept properly charged by using a special maintenance charger, such as a Battery Tender or equivalent. — K.F.


RV Manual

Q: We recently purchased our camping trailer, an Amerilite by Gulf Stream, which we like very much. My working experience has been maintenance of cars, trucks, heavy equipment, power plants, etc. Therefore, I know the importance of preventive maintenance. My question: Is there a book that covers the care and maintenance of a camping trailer?

Charlie Russell, Fairmount, Georgia

A: There are a number of good books on this subject. Our own Bob Livingston authored Trailer Life’s RV Repair & Maintenance Manual, which, although it is out of print, is still available through sources such as Amazon. A quick Google search for RV maintenance manual will also lead you to what you are looking for. — K.F.


The Tech Team

KEN FREUND: Ken is a former ASE Certified Master Technician, service manager and shop owner who has authored numerous books on automotive repair.

JEFF JOHNSTON: Jeff served as technical director of Trailer Life for 20 years and has been an RV enthusiast, mechanic and writer since he could hold a wrench.


RV Clinic from July 2015 Trailer Life

Jeff JohnstonKen FreundRV ClinicTrailer How-ToTravel Trailer How To

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