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RV Q&A: Lights Go Dim

Originally Published in Trailer Life Magazine

Q: I have a toy-hauler trailer, and the more lights I turn on, the dimmer everything gets. I replaced the converter, but there was no change. It still does this even while plugged into 120-volt AC shorepower. Do you have any suggestions?

Larry Jones, via email

A: The lights are powered from the battery bank, which is somewhat recharged by the power converter. A weak or nearly dead battery could cause this symptom, so it should be tested. Many auto-parts stores and other battery retailers will test the battery for free, if you bring it in, but it should be charged first. If your battery passes its test, then it’s possible that there’s a wiring problem that is not allowing power from the converter to get to the battery. Measure DC voltage at the battery when it is at rest with no load or charging, and then after the converter is powered up. Voltage should rise gradually from a baseline of about 12.6 volts for a fully charged battery at rest, to about 13.5 volts (or slightly more) while the converter is operating. If the converter is not boosting voltage, you might want to have an RV technician check it out, if you are not familiar with converters. — Ken Freund


Battery Maintainers

Q: I have been an avid reader of Trailer Life for a few years and enjoy the content. We have a 2009 Chevy Duramax-powered pickup that we use for towing, and of course, it has two batteries. I drive the truck only a few times in the winter and am a fan of battery maintainers — I use them for all off-season equipment. Can I hook the positive clip of the maintainer to the plus post of one battery and the negative clip of the maintainer to the ground terminal of the other battery? Will this charge both batteries at once, or do I need two maintainers?

Dale DeKay, Verona Beach, New York

A: Battery maintainers are a good idea any time a vehicle sits for more than a week or two, because there are so many small current draws from various items such as radios, computers and alarms, which will
discharge batteries during idle periods. Batteries also self-discharge over time. The setup you describe means your Chevy’s batteries are connected in parallel, so, yes, you can use one maintenance charger for both batteries.
— K.F.


Single Rear Wheel Versus Dual Rear Wheel

Q: I’m considering upgrading from my travel trailer and Ford Excursion to a fifth-wheel and pickup combination. The fifth-wheel I’m considering has a gross vehicle weight rating (GVWR) that’s just under the tow rating of a single-rear-wheel one-ton. I would prefer a a single-rear-wheel axle but don’t want to end up with an expensive truck that feels like it’s on the edge of control while towing. What differences can I expect in a single rear wheel versus a dual rear wheel?

Chris Lefevre, Milton, West Virginia

A: I’m glad to see you are considering these things before purchase. It’s difficult to predict exactly how your truck will behave with a trailer that is near its limit. Single-rear-wheel (SRW) pickups are convenient because they fit better in tight spaces, including garages and parking lots. Many dual-rear-wheel (DRW) pickups wind up banging into objects while maneuvering into tight spaces, and the rear fenders of used DRW trucks often bear the scars of such encounters. With an SRW truck, you need to buy only one pair of rear tires when replacement time comes. With a DRW pickup, you do get a more stable towing experience, and crosswinds and gusts from passing trucks don’t seem to affect a DRW as much. Also, if you get a flat rear tire while towing, you have more control than you would with an SRW pickup.

Modern pickups are extensively tested to their maximum ratings and should provide acceptable performance when loaded within those limitations. Most fifth-wheel trailers when loaded for vacation travel are not at their maximum weight limits, which is to your advantage. If you intend to be a full-timer with this combination, it’s more likely you’ll use most of that trailer’s GVWR. To really get a handle on this quandary between SRW and DRW, in addition to the trailer GVWR, you need to get the actual pin weight of the trailer — how much weight it will put on the back of the truck. You can then compare the rear gross axle weight rating (GAWR) of the two types of trucks. If you can’t get a loaded weight, which is likely the case, you can estimate how much weight will be added and what percentage of it will be on the pin. Then you can make an informed decision. — K.F.


Uneven Slideout

Q: We have a 2010 Jayco Eagle 321 RLMS fifth-wheel trailer. Once again, our RV is in for repairs. We have had problems with the 27-foot-long slideout since we bought it. They have now replaced the complete slide system with a newer, better one. Finally we thought we were good after having many interrupted and missed holidays. Not so! They have to put a wedge in to lift the rubber seal on the front portion of the slide; it extends ¾ inch at one end. They also need to repair the door to the bedroom, as it no longer closes. To me, this is not fixed.

Do you think this wedge will stand up to travel? And will it hold up if the front part is not level? It cost around $6,000 for this fix.

Roberta Whitbread, Surrey, British Columbia

A: A 27-foot slideout room is very heavy and probably twists the frame considerably when it is extended, especially with people in the room. However, it should be possible to properly align the slide mechanism to allow it to operate normally, without wedges. I’m not clear from your description if you had an independent shop do the work or if this was done by Jayco or a Jayco-franchised dealer under factory direction. A price of $6,000 seems like a lot, and I’m surprised you signed off on it and paid for the work if it wasn’t done properly. I suggest you take it back and demand that the slideout mechanism be repaired so that it works without Band-Aid fixes. — K.F.


Battery Charging and Surge Protection

Q: Recently, I read an article about an inline battery charger. If I remember correctly, it provided charging from the generator and the electrical hookup at a campground. It charged and/or did trickle-charging and surge protection as needed. I cannot remember what the unit was. I am looking for something that will fit this criteria.

Jeff Andrews, Arvada, Colorado

A: I don’t recall any battery-maintenance chargers having a built-in surge protector that could protect the RV’s electrical system from voltage spikes and surges. Maintenance chargers generally have lightweight wiring and work on the 12-volt DC side of the RV’s electrical system. Surge protectors have to protect the 120-volt AC side of the RV’s electrical system and require heavy wiring and protection circuitry. If anyone knows of such an item, we’d like to hear from them. — K.F.


Shocking Question

Q: We have a 2004 Mountain Aire 36-foot fifth-wheel. I use a 2003 Dodge 3500 diesel extended cab longbed pickup to tow it. It seems to be level, so do I need air shocks for this truck?

Gerald Hillmann, via email

A: If a truck rides level with a trailer hitched up and doesn’t have problems with ride or bottoming out while going over dips, it probably doesn’t need any modifications or additional parts. Air shocks are more for light-duty applications, and if they are installed and called upon to handle a lot of weight, often the shock mounts (which aren’t designed to handle loads in addition to shock-absorber damping forces) will bend or break. Therefore, for owners of larger and heavier vehicles such as yours, when it’s necessary to give the suspension a lift for level towing, air springs (aka air bags) should be considered, rather than air shocks. — K.F.


Tires Wearing Crooked

Q: We purchased a 2011 Salem trailer with tandem axles several years ago. Since that time, we have put fewer than 4,000 miles on it. The inside edges of all four trailer tires are incredibly worn, one to the point of being almost down to the cord. I have religiously checked the lug nuts to ensure they were tight and maintained 50 psi pressure in the tires at all times. Looking under the trailer, the axle seems to be a solid tube that can only sit in the machined lugs, so I have no idea how the wheels can be out of alignment. What can I do to rectify the situation?

Brian Wilkerson, Las Vegas, Nevada

A: There are two likely culprits. The wheel bearings might be adjusted too loosely. This would allow the tires to tilt out at the bottom. However, it’s more likely that the leaf-spring bushings are worn out, which can cause all kinds of alignment issues. These bushings are typically made from plastic and last only a few thousand miles (sometimes less) before they wear out, creating excessive movement. It is also possible that the trailer has bent axles or spindles, maybe from hitting potholes or curbs. If the wheel bearings aren’t loose and the bushings look OK, have an alignment shop check out the trailer thoroughly. From there, you can make an informed decision on how to rectify the problem. — K.F.


Anti-Sway Hardware

Q: I am new to pulling a trailer, although I now have more than 8,000 miles of towing experience behind me. I really enjoyed the trip but sure am tired of the trailer sway. I find that I am always looking in the mirror for a passing truck, bus or motorhome. I am considering the Hensley Arrow hitch and would like to know your thoughts or other ideas. I have been using a weight-distributing hitch and anti-sway bar. My tow vehicle is a 2014 Ford F-150 SuperCrew with EcoBoost.

Lee Phillips, Weston, Vermont

A: There are numerous anti-sway-type weight-distributing hitches on the market, and each has its strong points. The Hensley Arrow is the most expensive and also the heaviest, but it works like a champ. We’ve towed with it numerous times and have felt how well it worked for us. If you can handle the cost, and the hitch weight won’t detract significantly from your gross combination weight rating (gcwr) or add too much hitch weight carried by your truck, it’s a great choice.

It is also, of course, important to make sure your trailer is properly loaded with at least 11 percent of its weight on its hitch, and the hitch must also be properly adjusted to ensure stable towing. The trailer must also be properly matched to your truck’s tow rating, as even an Arrow hitch won’t overcome other mechanical or setup deficiencies, nor should anyone use it as a Band-Aid to solve other problems. — Jeff Johnston


Towing Limits

Q: We have a 2013 Ford F-150 SuperCrew 4×4 with a 5.7-liter EcoBoost engine and a 3.31 rear end. The truck has a 6½-foot shortbed. I have been looking at towing weights and would like to know if I can tow a KZ Durango D281RLT fifth-wheel without harming my truck. The Durango lists its unloaded weight as 8,510 pounds and its dry hitch weight of 1,490 pounds. The dry axle weight is 7,020 pounds, and net carrying capacity is 1,990 pounds. The GVWR is 10,500 pounds. I think I am approaching the weight limits with this trailer, but could I successfully tow it without damaging my truck?

John Stineman, Lincoln, Nebraska

A: There’s no 5.7-liter engine in the Ford lineup for the 2013 F-150, but the 3.5-liter V-6 is Ford’s EcoBoost engine and also matches up with your truck and axle-ratio description. That truck body and powertrain combination can be rated to tow 9,200 pounds. I’m sure you’re aware that the trailer manufacturer’s “dry weight” figure is nothing but an approximate starting point; it doesn’t include water, LP-gas or cargo you take along, and it often doesn’t include some factory-installed options. Of course, you also need to consider the weight of the passengers and cargo you haul in the truck that is applied to the setup’s GCWR.

In other words, the trailer you have in mind is too heavy for your truck as configured. We recommend that you shop for a trailer with a GVWR of around 9,000 pounds. That way, you can load the trailer down all you want, and as long as you don’t exceed its GVWR, the combination will be appropriately matched, and there’s less risk of overloading the truck. Considering the shortbed configuration, you should think about getting a sliding fifth-wheel hitch to prevent trailer-to-cab interference problems during tight turns. — J.J.


RV Cover — or Not?

Q: We have a 30-foot Cameo fifth-wheel that we winterize and store at our residence under a high-end RV cover. Last year, due to an unfortunate accident, we needed to have the roof replaced and were told not to cover the RV. This was from a reputable RV-repair place. We recently had the RV detailed prior to storing it for the winter. Again, we were told not to cover the RV. This is confusing, as all the RV suppliers and dealers promote covering your RV to protect it from the elements when not in use. When questioned, both businesses stated the covers wear down and ruin the rubber roof. What is your take on this? Are they correct?

Carol Reijm, Mount Vernon, Washington

A: If you choose a good-quality cover, and fit and install it according to the manufacturer’s instructions, you shouldn’t have anything to fear for your roof. The fabric is made to be compatible with RV roof materials and, as such, should cause it no harm when properly used. If in doubt, inquire with the RV-cover manufacturer to check any damage warranties that may apply.

It’s possible the dealers you spoke to who cautioned about cover use may have been referring to cheap one-size-fits-all covers or blue plastic tarps that you see strapped over RVs here and there. Ill-fitting covers like these can flap in strong winds, and that harsh plastic material can cause damage to an RV roof, endcap and side wall. — J.J.


Backup Thump

Q: I own a 1997 Holiday Rambler Aluma-Lite fifth-wheel pulled by a V-10 Dodge 2500. I have started to notice a slight thumping noise when backing the trailer into my storage building. I’ve been towing the trailer since 2009, and this started last summer. It is most noticeable as the truck is turning to be in alignment with the trailer. I thought it was the surfaces between the hitch and fifth-wheel, so I applied a generous amount of general grease. The problem persists. Do I need to use a heavier grease? Is there a suggested type or grade to use?

Tom Green, Angola, Indiana

A: Any time you’re towing a fifth-wheel and turning the truck relative to the trailer, there’s going to be some noise, Tom. If you’ve been towing with the same hitch since 1997, there are bound to be some moving parts that are exhibiting wear. Even with adequate lubrication on the base plate, there’s some rotating stress on the hitch, and that noise could come from the kingpin shifting in the saddle, the saddle shifting in the base or the base shifting in the mounting rails, for example. If you give the hitch a thorough inspection, you may well discover some moving parts with more clearance than you’d expect. If you have any doubts about those parts, take the hitch to a qualified dealer and have a technician inspect it and perhaps recommend replacement parts, if needed.

As for the right kind of grease to use, any heavy bearing grease should do the job, but you can also check the hitch manufacturer’s instructions for specific recommendations. — J.J.


Converter Disconnect

Q: Will it harm the power converter if I disconnect and remove the battery while my RV is connected to AC power?

Dave Meekins, Blythewood, South Carolina

A: This won’t harm your converter at all, Dave, but you might want to make the battery disconnection short-term only. The battery acts as something of a reservoir and “buffer” for the 12-volt DC power coming from the converter. With the battery in place, in effect, you’re operating on the 12 volts supplied by the battery, and the converter is simultaneously charging the battery to some extent. Without the battery, your RV is operating strictly on the converter output, and that power may not be as clean and consistent as that which comes from the setup with the battery. You won’t harm the converter, but it’s still best to keep that battery as part of the system. — J.J.


Boosting Stopping Power

Q: In the November 2015 issue, you answered Bob Smith’s “Can’t Stop!” question about his inability to stop when towing his 2013 CrossRoads Cruiser fiver. While his Ram brake controller may be part of the issue, I think it may have something to do with the trailer.

We have a 2014 CrossRoads Cruiser 35SS and tow it with a 2013 F-250 diesel. In only 2,600 miles of towing, I became concerned that the trailer brakes were underperforming. At a controller setting of 7 to 8 (high for a new trailer, I think), any but the gentlest of stops brought the sensation of being pushed by the trailer. One hard stop and close call really scared us.

Two weeks ago, I had the brakes changed out from electric drum to electric-over-hydraulic disc brakes. The test drive was remarkable. At a controller setting of 6, easy stops were smooth and controlled. Firm stops from 30 to 35 mph were sure and without any pushing. A hard stop from 45 mph was incredibly strong, with the combo feeling like a single unit.

I feel a lot more comfortable now. Of course, the best practice is to drive easy, leave lots of room for stopping and pay attention. But when some knucklehead cuts you off, you don’t want that sinking feeling that the brakes aren’t doing the job.

Jay Six, Arlington, Texas

A: There’s no substitute for a set of properly sized and adjusted brakes, Jay, along with a properly adjusted brake control. Thank you for passing on your experience with an aftermarket disc-brake setup. — J.J.


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 February 2016 Trailer Life

Jeff JohnstonKen FreundRV ClinicRV Questions and Answers

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