Tweaking an Icon: Upgrading a Jeep Wrangler
Outfitting the Wrangler Unlimited for Towing
and Off-Road Travel
Article Date: June, 2012
Jeep's Wrangler has been around seemingly forever. While its trademark seven slot grille remains basically the same,
today's Wrangler has seen a ton of improvements since the 1941 Jeep that carried our armed forces to victory in World War II.
One new addition was the Wrangler Unlimited, which offered a longer wheelbase and four doors. The Wrangler Unlimited
quickly became a hot seller with those buyers who wanted a Jeep but needed more practicality for everyday use.
RV owners with motorhomes quickly appreciated this, and the Wrangler Unlimited is now a common sight at many campgrounds.
The Wrangler is easy to tow behind a motorhome and is the perfect vehicle to take into town for supplies or go exploring off-road at the nearby
scenic areas typically near RV parks and campgrounds.
Wranglers are ideal for towing behind an RV and don't require any driveline disconnects or transmission lube pumps. Just connect the Jeep
to the RV, slip the transfer case into neutral, and go.
Stock Wranglers are capable but replacing the poly bumpers with heavy duty off-road bumpers and other components can turn the
Wrangle into a true off-road machine.
Normal tow bar base plates mount to the Jeep's frame and extend below the front bumper. This puts them in harm's way should
you get them hung up on a rock or bottom out if driving in deep ruts. Bending up a base plate means you won't be able to tow your Jeep home, so that
limits what you can do with your Jeep in the dirt.
The best choice is to find a bumper strong enough to handle a set of tow bar mounting brackets, so that you can connect your
bar directly to them. That way the area beneath your front bumper is clear and you'll maintain better approach angles and prevent damage to your
towing setup. Plus, by not requiring a base plate you can save that money and apply it towards a good front bumper design.
The original rear bumper was molded with a recess to aprovide clearance for the spare tire.
After doing lots of research I decided to use Rock Hard 4x4 products due to their great looking design and a commitment to
quality and strength. The company also had custom tow bar brackets available for its front bumpers that fit either Blue Ox or Roadmaster tow bars.
To handle protection against damage from rocks and other objects when off-roading, I ordered up a complete set of skidplates
from Rock Hard, as well as a set of Mopar Rock Rails from my local Jeep dealer. To connect the Jeep's rear lights to the motorhome I installed a
Tow Daddy Plug-N-Tow module. The Tow Daddy module is the simplest and safest way to tie your existing lights into the RV's lighting feeds when towing.
Finally, an M&G auxiliary braking system was selected. It utilizes the motorhome's air brakes to proportionately operate the
towed vehicle's brakes. The module is fully contained under the Jeep's hood and does not tap into the Jeep's electrical or hydraulic braking systems.
It's failsafe and foolproof.
Installing the Bumpers
The rear bumper was pretty straight forward. Unbolt the old one and replace it with the new one. Be sure to get an extra hand
or at-least a floor jack to help as these bumpers are heavy.
The front bumper was the heart of the upgrade. Once the original plastic bumper and fog lights were removed and a few small
modifications to the frame were completed, the new Rock Hard bumper was installed. Then it was time to move on to the winch.
I used a floor jack to lift the substantial Rock Hard 4x4 bumper into place. The bumper included a hitch receiver and was fitted with
D-ring clevises for retrieval operations.
The bumper has a large opening for the winch to set into. It will accommodate the huge Warn Powerplant winch we chose, but
it fills the entire area and requires a few small modifications to fit properly. Once the winch was in and safely bolted up, the tow bar brackets
The factory bumper and the Rock Hard bumper mount with eight bolts. Utilizing four of these bolts to mount the tow bar
brackets is the strongest (and easiest) way to get the job done. So that's what I did.
Next a few holes were drilled to install the socket for the tow lighting umbilical cable as well as a connection for
the M&G auxiliary brake air line from the motorhome. A breakaway switch was then installed to activate the brakes should it ever become
disconnected from the motorhome when towing. Finally the D-ring shackles were hung on the front and a snap on license plate bracket was
mounted on the winch roller fairlead to make it legal.
A spare tire adaptor plate was included to raise the spare tire enough to clear the Rock Hard rear bumper.
The Wrangler's muffler is transversely mounted behind the rear bumper. A Rock Hard muffler skid plate was added to protect this
area when exiting downgrades or climbing over rocks.
A set of Mopar Rock Rub Rails was ordered from the local Jeep dealer to protect the rocker panels from damage.
The original Jeep fog lights were mounted in center of the front bumper and held in place with four hex head screws.
The Rock Hard front bumper is designed to accept the original Jeep fog lights and has pre-tapped holes to accept the mounting screws.
The Rubicon has an electric front sway-bar disconnect mechanism to aide articulation in off-road situations. This unit normally is
located just beneath and behind the front bumper in a vulnerable location. The Rock Hard front bumper is formed to fully protect the
A vacuum booster pump is part of the new 2012 Wrangler powertrain. It is located near the end of the driver's side front frame rail
and will interfere with most aftermarket front bumpers. Rock Hard supplied a custom bracket to relocate the pump so that it was out
of the way.
With all the extra weight added from the winch and bumpers the Jeep was now sagging in the front. To alleviate this I
installed a Terraflex front coil spring spacer kit, designed to raise the Jeep 2 inches. This gave us back the 1-1/2 inches that we lost and
raised it up an extra half inch to reduce the factory tail high rake and make it appear more level.
Towing a small vehicle like a Jeep behind a large, heavy motorhome generally doesn't add a significant amount of stress
to the RV's breaking requirements. But, there are times when I've nailed the brakes and without the towed vehicles auxiliary brakes, that extra
stopping distance made the difference between a near miss and impact.
Plus, if the towed vehicle should ever come loose you'll want a breakaway system to lock up those brakes to prevent it
from becoming a runaway ballistic missile. The M&G auxiliary braking system that I chose utilizes the motorhome's air brakes but an optional
air compressor unit is available for gasoline powered motorhomes with hydraulic brakes.
The Rock Hard full-width front bumper offered a low winch mounting location to provide maximum airflow to the radiator. This bumper can
accommodate the massive Warn Powerplant winch with integral air compressor.
In order to install the M&G system you need to remove the master cylinder from the vacuum booster. The M&G module is
then installed between the two units. An air-line is then connected to the motor home while another line is fitted to the M&G module and run to
the front of the Jeep. A quick disconnect air-line is used to connect the two brake systems for towing. As the motorhome's brakes are applied,
air pressure enters the M&G module and spreads two pistons apart to energize the master cylinder and apply the Jeep's brakes. An optional
breakaway valve is connected to a small air tank so that the brakes may be applied in the event of a breakaway.
While the Rock Hard front bumper had just enough room to squeeze the Warn Powerplant in, the factory bumper mounting brackets
intruded slightly into that area. A disc grinder was used to trim the brackets a bit to open up that area.
Rock Hard offers tow bar adaptor brackets for either Blue Ox or Roadmaster tow bars. These brackets bolt right to the bumper at its
frame mounting locations and eliminate having a low slung tow bar base plate that can get damaged on off-road trails.
The top surface of the front bumper offered plenty of room, making it easy to install my tow lighting socket, an airline connection
for the braking system, and the breakaway switch.
Wiring it all Together
Now that everything was bolted into place it was time to wire it all up. The Tow Daddy Plug-N-Tow system is designed to
plug right into the Jeep's tail light harness so no splicing is required. I placed the module behind the left taillight and plugged it into both
rear lights. The wires that feed the system were then run up to the front bumper area, where they were connected to the lighting socket installed
in the front bumper. I also ran a 12-gauge battery hot line with circuit breaker from the RV to the Jeep to keep the Jeep's battery charged when
towing. The winch was then connected to the battery terminals and the receiver for the winch's wireless remote was connected.
The M&G auxiliary brake module mounts between the master cylinder and vacuum booster. In order to make room for the M&G module the
small plastic wall was cut away so that the brake assembly could move forward the required amount.
A charge line between the RV and Jeep allowed the motorhome's battery power to keep the Jeep's battery charged when towing. A 20 amp
circuit breaker was installed near the battery to provide overcurrent protection.
The Tow Daddy lighting setup is state of the art. It offers plug and play connections to your tail lights without requiring any cutting
of those wires. The control module is equipped with status LEDs and provides back-feed protection to automatically switch between the
lighting circuits used when towing or during normal driving.
I disassembled our old Blue Ox tow bar, sandblasted it, and painted it with Eastwood gloss black ceramic chassis paint. All
worn parts were replaced and I even picked up a shiny new set of locking hitch pins to replace the pitted ones that I had been using for years.
Once done I hooked the newly improved Jeep to our motor home, checked the lights and set off for a test drive.
The Rubicon performed admirably throughout the trip. We never even knew it was back there when towing and there was no tire
wear, death wobble, or other issues. We just hooked it up, put the transfer case into neutral, and were ready to go.
The Jeep was very well mannered in city traffic and gave an excellent ride that one wouldn't expect from an SUV designed for
serious work. It was equally at home on Montana's high-speed highways, and our fuel economy had improved over previous Jeeps. Once we got off the
beaten path in Wyoming's Bighorn Mountains, the off road prowess of the Rubicon really shone. We drove through rocky terrain without fear of damage
and the Wrangler was just plain unstoppable.
All in all, it's the perfect vehicle for the owner of a motorized RV who wants to blend exploring and off-road fun with
When connecting the tow bar it's important to keep the tow bar as close to level as possible. Excess angle will allow vaulting or
submarining during a sudden stop.
The D-Ring shackles on the Rock Hard front bumper made for perfect safety cable connection points. The breakaway switch, lighting
umbilical, and brake line were all clustered in a central location on the bumper.
Preparing the Wrangler in this fashion yielded the perfect balance between towing and off-road use and made for a very versatile
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