May 8, 2017

TT #96 Choosing a New Tow Vehicle: Preparing it to Flat Tow (#1)

By: Rob Lowe

Featured Picture

Most RVers tow a vehicle behind their coach and the convenience of flat towing on all four tires makes using a towbar and baseplate (bracket) the preferred method. That’s not to say that dolly towing and trailers are not common, especially with those that choose among more than one vehicle to tow or those that prefer a vehicle that is not flat towable. However, storing a dolly or trailer at a destination often makes this selection less convenient.

We just went through the process of selecting another tow vehicle and getting it ready to tow. I’ve chatted with many of our customers that have also recently gone through the same procedure. They expressed their concerns and joys about it. I thought it might be helpful to look at what has changed and some lessons learned from assisting RVers over the years.

Selecting a New Vehicle:

While it is possible to find a good used vehicle to tow, I’ll limit my article to selecting a new one (trhe current model year or one older). This will help focus us on some of the changes. Priority number one is to look for a vehicle that is flat towable. There are many and two handy references are the Motorhome magazine’s Annual Dinghy Towing Guide updated annually and included with the January issue of Motorhome magazine. FMCA also publishes a similar "Towables for 2017” article also published in January each year.  Both list vehicles that are approved by their manufacturers to flat (or Dinghy) tow behind a motorhome together with the requirements and limitations set out by the maker for doing so.

It is noteworthy that some of the rules of thumb we used to follow (such as any manual transmission vehicle is flat towable) are no longernecessarily the case. Powertrains have changed and some manufacturers no longer support flat towing of their vehicles at all. In a recent conversation with an automotive engineer he reminded me that the automobile business is a worldwide one with many vehicle designs emanating from countries in Europe, Australia or the Far East where flat towing does not enter the picture. A world platform vehicle design may not have anticipated the North American need to flat tow.

Powertrains are increasingly designed for fuel efficiency, the transmission specified may not be lubricated when towing, thereby preventing this vehicle from being flat towed. It is common with newer vehicles to require fuses to be removed or for the negative battery cable to be removed while towing. In the past, this requirement was to eliminate battery power drain from multiple circuits however lately it is more likely required because major system(s) on the vehicle will continue to function even with the vehicle turned off. An example is the 2014 and newer GMC & Chevrolet pickup truck (and similar truck based vehicles) that have electronic steering with sensors for steering wheel position embedded in the steering column. If the battery remains connected when the truck is towed around a corner, the wheels will turn however the steering wheel will not and the electronic power steering will try to straighten the wheels out. Severe, non-warranty damage will occur to the steering column. Increasingly, these types of systems are showing up in newer vehicles as computer control replaces mechanical functions.

For years, Jeep owners prided themselves on simply placing the transfer case in Neutral and towing. Jeep Cherokee’s from the 2014 model year and newer have had a tendency for their front wheels to oscillate side to side under certain conditions while being flat towed. Jeep introduced a retrofit kit that provides power to the power steering motor to maintain stability. A switch located in the console storage bin must be turned on when towing and a fuse inserted into a newly installed underhood fuse holder. The fuse must be removed and stored while driving, unless a switch is installed. Our RVing FuseSwitch™ is one product which works well in this and any fuse removal applications. These and similar factors leave the RVer responsible for checking the owner’s manual of the prospective vehicle to be towed and double checking with the dealer’s service department (often using the Vehicle Identification Number (V.I.N.)) to confirm that it is flat towable and what the specific requirements are for towing it.

Baseplate (Bracket) Installation on Newer Vehicles:

Once you’ve selected a prospective tow vehicle, check to ensure that the baseplate (or bracket) and wiring kits are available to setup the vehicle for towing. Baseplates (or brackets) have come a long way from their original simple welded designs. The one we installed was a piece of art with gentle curved metal support and superb welded seams. Computer designed and cut, high quality welding and accommodation for the wiring connector, brake system breakaway switch and safety cables to retain the unit in the event of a bolt failure are all part of the newer design. The detailed instructions included many photos, although I recommend downloading the online version and printing it in color since some of the detail is far more visible in color. It is also possible to zoom in on the photo to get even more detail when required. Most installations will require removing the front fascia of the vehicle which may seem intimidating to a do-it-yourself person however rest assured that reading and following the instructions and having an assistant to help will greatly ease the work.

With many electronic systems utilizing sensors mounted in the front fascia, one would think that there would be a lot of wiring to disconnect. There is a lot of wiring, however it was all neatly bundled in looms and terminated in a single, multi-pin connector. This connector (on a GM vehicle) had a red tab that was slid away from the locking pin and then a screwdriver is inserted to lift the black hook from the locking tab. It sounds more difficult than it is. See the photos for a reference (although these were located on the taillight).

Cutting off the metal sections specified requires a sharp metal saw blade (we used a Sawzall® reciprocating saw) and care. Often there are some plastic parts that will be removed and not reinstalled since the baseplate takes up the space occupied by those components. Holes for bolts will need to be drilled on many installations. I recommend using gold colored titanium drill bits and lots of cutting oil when drilling through the hardened steel frame of the vehicle. Most baseplates include all the proper hardware to complete the installation. Use it, since the grade chosen by the supplier is best for the job. If there is a shortage, let them know and get everything before you begin. Ensure you apply red Loctite® to all bolt threads as instructed, then tighten all bolts and nuts to the torque specified.    

The challenge in the installation is cutting the access area in the fascia for the removable baseplate tabs to fit into the baseplate ‘ears’. There will always be variations from the photos provided by the baseplate maker, so it is a slow methodical procedure to cut away enough material to allow the fascia to be reinstalled while not going too far. This is where having two people really provides the needed assistance and judgment to see what needs to be done. Holding the fascia into position yet having the protrusions on the baseplate alter the location makes the process tedious. However eventually there is that eureka moment when there is sufficient clearance and the fascia fits. Reinstall the fascia after ensuring the wiring for the towed vehicle lighting, trickle charge lines, any braking system air lines and wiring, together with the breakaway switch wiring are run in place and up to the engine area. I recommend installing plastic loom over the wiring to protect it and to hide it from view when looking through the grill area afterwards. With the fascia reinstalled, it is a minor task to align the breakaway switch and the connector posts to fit through the grill area. A handy way to align the posts is to use a small diameter deep socket on a breaker bar. Slide the socket over the post and rotate the bar so it cannot bend in the direction you want to bend the post, then apply pressure down or up to move post into position. Do the same for the second one ensuring that the mounting holes for the connector are aligned and parallel to the ground. Complete the installation of the wiring and braking system, test everything for correct operation and you are almost ready to flat tow your new vehicle.

Tow Bars:

Caution: If you’ve selected a larger vehicle such as a pickup truck or full-sized (truck based) SUV, the tow bar you have been using may not be the best one to tow the new vehicle. With increasingly tighter RV turning angles (now up to 60⁰) combined with wider tow vehicle frame widths, which make the towing tabs wider apart (often 32-35” (81-89cm)) and the vehicle closer to the RV when towed, it is possible for the rear corner of the RV to impact the towed vehicle’s front fenders on tight turns. The solution has been to increase the tow bar arm length by 2” (5cm) to restore the towed vehicle to a safe distance behind the RV. Blue Ox introduced their Avail with longer arms and patented non-binding latches while Roadmaster recently introduced a Nighthawk towbar that not only has longer arms and tracks for the wiring and safety cables, it is the first to feature patented LED lighting on the arms.  Both designs show that innovation is alive and well in the towing industry!

If you are going to use your existing towbar, it is wise to have it examined by a professional to ensure that it is still safely within the design specifications and that the nylon washers and other components are not too worn. The shafts wear down and the assembly becomes loose. If the bar flops down after being left in a vertical position on the RV, then wear is evident. We get used to it slowly loosening up however a trained eye can see issues that make it unsafe. It is not worth the risk when preparing to tow a new vehicle to use an existing marginal and potentially unsafe tow bar. I’d recommend carrying out the recommended annual maintenance and having it professionally inspected every other year.

In the next Tech Tip, I’ll review installing the wiring on your new towed vehicle so you will be all prepared to tow.


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