Preparing our 2010 Miata NC-2 for RV Towing
This page shows pictures of MY installation of the
Roadmaster baseplate and brackets to our Miata NC
(NC is for the model years 2006 - 2011)
NO circumstances should Automatic Transmission
We bought our 2000 Miata 5-speed roadster in 2006 and drove it daily for 5 years and 50,000 miles. We towed it an additional 35,000 miles behind our RV.
was such a wonderful car to drive and to tow, that we jumped at the opportunity
to trade it for a 2010 Miata PRHT (Power Retractable Hard Top).
Although this car was a 2010 and had 1000 miles on it, it came to Dallas from
a California Miata dealership and had never been sold or titled.
Rather than the formidable task to design and build towing brackets for the front of the new Miata (as I did with our previous NB Miata), I decided to buy a set of Roadmaster Miata NC towing brackets. Roadmaster does NOT make their towing brackets for any Miata newer than a 2008.
I found and bought a set of "pre-owned" (= used) from a full-time RVer. He and his wife had just stopped full timing and sold their 2006 Miata NC.
I took a gamble that Miata had not changed the chassis and that the brackets for his 2006 would fit my 2010 PRHT.
We quickly made a deal and he shipped his Roadmaster brackets and all of the hardware to me.
long as I was using Roadmaster towing brackets, it didn't make much sense for
me to design and build my own tow bar to interface with it.
HERE are the tow bar and the Miata brackets mated up for the first time. Everything fit perfectly.
Even having the the Roadmaster Installation manual in hand, I spent a couple of days disassembling, installing the brackets, and reassembling the Miata.
found it best to take off the front wheels and dropping both the front
and rear sections of the wheel well liner.
|When removed, the front bumper cover looks like a Halloween mask|
The 3 piece Roadmaster baseplate is easy to install, but nutplates and bolts must be inserted more than 16" into the frame through the large round holes below the headlights. This hardware bolts the baseplate brackets to the unibody chassis.
When purchased from Roadmaster the nut plates have long bendable wires attached to them. Since my baseplate was removed from another car, I used duct tape and a coat hanger. Not too hard to do. I also installed all of the 1/2" bolts with the threads OUT of the chassis rather than Roadmasters threads IN and nutplates inside the chassis approach.
I used flat washers under the bolt heads and used flat washers under all of the nuts and applied Loc-Tite to all of the bolt/nut thread interfaces.
|Below is a trial
fit of the front mask with the towing baseplate in place.
Holes for access to the tow bar attachment tubes must be cut in the grille
Below shows how the baseplate tube protrudes through the grille. Since this is only a trial fit, the baseplate will be de-rusted & painted before final installation.
Roadmaster provides a small lug on the inside of the tube for the attachment of a safety chain/cable. I was not satisfied with that arrangement and went with a separate attach point for my safety cables.
|I used rubber crutch/cane tips to plug the baseplate holes to keep out dirt & rain.|
Here is how it looks when all reassembled. The baseplate is nearly invisible. The electrical connector recepticle is not yet installed.
|This bracket plugs into the baseplate tubes through the grill and rotates 90 degrees to lock it in.|
|After the bracket is inserted and locked, a crossbar between the two sides is locked in place. Then tow bar is attached between the two large tabs with the 3/4" holes..|
MY coiled safety cables hook to REMOVABLE 1/2" welded eye bolts that are screwed into threaded receptacles that I installed in the baseplate cross bar.
Plastic "funnels" made from soft drink bottles guide the end of the welded eye bolt into the threaded recepticle which is located 6" behind the grille.
Here is how it looks when ready to hook up to tow.
The center electrical cable connector is painted black and is wired to diodes which activate the rear tail parking and brake/turn lights.
There is one other serious and important issue to deal with before towing a Miata NC. That is the issue of the Key-in-the Ignition.
When towing any car, the front wheels of the car MUST be free to turn to follow the towed vehicle.
With the NA and NB Miatas, one could leave the key in the igntion switch and leave the switch in ANY position (INCLUDING lock) as long as the key was NOT REMOVED from the lock. It was the act of REMOVING the Key from the lock that activated the steering wheel lock which prevented the front wheels to turn to follow the tow vehicle.
NOT SO with the NC Miata. In the NC, the steering wheel lock will ONLY be released or deactivated when the key is turned OUT of the lock position and into the ACC, On, or Start positions.
Towing the car with the key in the ACC position means that all of the car's accessories (radio, wipers, heated seats, heater/AC blower, etc.) are active and drawing power from the Miata battery.
Towing the car with the key in the ON position means that not only are all of the car's accessories are active, but that the ignition and dash instruments are active. This means that as you tow the Miata, the Speedometer/Odometer WILL be recording miles towed as miles driven.
There are several ways to handle this Key-in-the-Ignition situation. One is to disconnect the battery. Disconnecting the battery means that power will be lost to the radio and the car's main computer. All of the radio preset stations will be lost as well as much of the driving and engineknowledge that the main computer has learned will be lost.
Another, but FAR more complicated, way to handle the Key-in-the-Ignition situation is to permanently disable the steering wheel lock.
THAT is what I did. This link will take you to a page that will show, in detail, how I disabled the steering wheel lock which allows me to tow the car with the igntion in the LOCK position and have the steering wheel free to turn.
While I have not yet towed the Miata NC behind our RV, I did hook it up to our Suburban and and tow it around the block.
|Rather than use the typical spring clips that smash ones fingers, I am using keyed-like locks at all of the tow-bar to baseplate junctions. The tow-bar will also be locked to the hitch receiver.|
Because there are 9 "joints" from hitch receiver to baseplate, there is much more front-to-back "slop" than there was in my NB towing set up with it's 3 joints. The lack of "tightness" will take some getting used to, but in the end it will work just fine. That is a small price to pay for being able to take our Miata PRHT with us.
We leave on a 6,000 mile trip on 6/27/2011. I'll post the results.
! Update !
On 8/1/2011, we returned from a 32 day, 6,300 mile, trip. The basic trip route was from Dallas, TX, to Kalispell, MT, to Sault Ste. Marie, MI, and back to Dallas, TX. We also drove the Miata alone another 1.300 miles.
The Miata towed wonderfully! Because this Miata is about 75 pounds heavier than our 2000 Miata, I was VERY conscious of my following distance, although I didn't notice any difference in the ability to stop.
Towing a Mita is a JOY!, especially this one with its retractable hardtop.
Please feel free to with any questions
CLICK HERE for pictures of MY personal design and build of the baseplate and tow bar that was needed to tow our 2000 Miata NB (1999 - 2005) for 35,000 miles behind our RV.