Wiring Recommendation for Flat Towing a 2014 Ford Flex
Updated 05/15/2020 | Published 05/13/2020 >
Products Featured in This Question
Question:
Im setting up my 2014 Ford Flex to be flat-towed behind my motorhome. Im looking at the tow bar wiring systems, and I see 5 different options! They all look to be universal I take that to mean: not plug-n-play, and I understand that part, but why would I just one over the other? My Motorhome has both a 7-blade round plug, and the flat 4. Is it just preference for how the connection is made from the motorhome to the front of the Flex? Is one kit easier to install than another? Thanks for your help!
asked by: Chester
Expert Reply:
That is an excellent question. There are multiple options of wiring available for flat towing any vehicle and it can be really overwhelming when doing research. A lot of it stems from wiring kits being fairly universal so when a manufacturer comes out with a fit then it can technically be installed on multiple vehicles.
For your 2014 Ford Flex I recommend using the Roadmaster Flexo-Coil Wiring Kit # RM-15267 because it has the 7-Way that plugs into your motorhome but then it also has a 6-Way for the Flex side. This allows you to activate your vehicle lights as well as add the Charge Line Kit # RM-156-25 to prevent your battery from dying (the manual states to run the engine every 6 hours to prevent the battery from dying).
You can definitely install something with less wiring like the Universal Hy-Power Diode Kit # RM-154, but then you'll have to make sure you set a timer and stop to run the engine every 6 hours.
So ultimately some it if comes down to personal preference while others come down to convenience. Please note that for a complete flat towing setup you will need a base plate kit, tow bar, safety cables, vehicle tow bar wiring, a supplemental braking system, and possibly a high-low adapter. If you don't have everything already then I recommend the following:
Direct-Connect Base Plate Kit - # RM-524435-5
Nighthawk All Terrain Tow Bar - # RM-676
Towing Combo Kit - # RM-9284-2
Brake Kit - # SM99251 (hydraulic motorhome brakes) OR # SM99243 (air motorhome brakes)
Charge Line Kit - # RM-156-25
Relay Kit - # RM-88400
The direct-connect base plate kit pairs with the Nighthawk All Terrain tow bar to give you one of the nicest and easiest to use combinations on the market. The tow bar also comes with safety cables and part of the wiring kit that we initially talked about. By adding the combo kit we then get the rest of the wiring plus a cover and locks for the tow bar to help it last a long time.
The brake kits I recommended are the best in the business and are extremely easy to set up after the initial installation. The charge line kit is for convenience and the relay kit is to make sure your Flex lights work properly while heading down the road.
A lot of flat towing setups might require the use of a high-low adapter to keep the tow bar level while towing a vehicle. I have linked a helpful article for you to reference to see if this applies to you. If it does then I have also linked our selection of adapters for you to filter through.
Product Page this Question was Asked From
Roadmaster 4-Diode Universal Wiring Kit for Towed Vehicles - 7-Way to 6-Way Coiled Adapter Cord
- Flat Tow Wiring Harness
- Splices into Vehicle Wiring
- Diode Kit
- Universal Fit
- 7 Blade to 6 Round
- Roadmaster
more information >
Featured Help Information
Instructions
Miscellaneous Media





Continue Researching
- Shop: Vehicle Tow Bar Wiring
- Q&A: Recommended Flat Tow Setup For 2022 Ford Escape Plug-In Hybrid Using Blue Ox Tow Bar
- Article: Best Vehicles to Flat Tow Behind an RV
- Article: Trailer Wiring Diagrams
- Article: Flat Towing Package for 2007-2018 JK Jeep Wrangler and Wrangler Unlimited
- Q&A: Which is Better Roadmaster or Blue Ox Tow Bar
- Article: Must-Have Flat Towing Components
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Q&A: Recommended Flat Tow Parts for a 2025 Jeep Wrangler Sport Towed By A Tiffin RV w/ Quick Connect Air
- Q&A: What is the Difference Between the Blue Ox Patriot BRK2019 & BRK2022?
- Article: Wiring Trailer Lights with a 7-Way Plug (It's Easier Than You Think)
- Q&A: Recommended Flat Towing Set Up for a 2026 Ford Maverick Hybrid
- Q&A: Recommended Parts for Flat Towing a 2025 Ford Maverick
- Q&A: Can I Run the Blue Ox Patriot Braking System On It's Own 6 Volt or 12 Volt Battery?
- Article: We Used 34 RV Tow Bars, and These are the Best for Flat Towing

