2021+ Jeep Grand Cherokee L Baseplate/Air Force One Installation
This post describes tips for removing the front fascia on a 2021+ Jeep Grand Cherokee L (GC-L) model, in preparation for installing a baseplate used for flat towing. This part of the project applies to the installation of any brand baseplate.
Also discussed in this post:
- Roadmaster 521485-5 Baseplate Installation Notes
- Additional Baseplate Ideas
- Demco Air Force One Installation Notes
- Demco Air Force One Brake Indicator Light Notes
- Demco Air Force One Breakaway Switch & Toad Charge Wiring Notes
- Electrical Wiring Tips for the Umbilical Connector
- Issues Flat Towing the 2021+ GC-L
- Notes Regarding Flat Towing the 2021+ GC-L
No matter which baseplate brand you are planning to install, the fascia removal is a universal requirement and oftentimes the most intimidating part of the project, especially on a brand new vehicle – at least it was for me!
Not to worry tho, of the three vehicles on which I have done a fascia removal/replacement, the Jeep Grand Cherokee L turned out to be the easiest. The other two were a 2007 and 2013 Honda Odyssey.
Note: I save all the OEM parts and remove the baseplate and restore it to factory when selling the vehicle. I also purchase and replace any grill parts that had to be cut during installation, this makes for an easier sale or trade.
In this procedure I am going to follow the Roadmaster instructions for the Overland (part # 521458-5 11/17/21) which I found to be a bit more complete than the BlueOx instructions. Below I have called out the step numbers in the Roadmaster instructions and added additional notes, tips and in some cases, videos of how to complete that step. To follow along download the Roadmaster 521458-5 instructions here.
Click on the photos for a larger version.
Steps #1 & #2 – While not absolutely required, I suggest obtaining a push pin clip removal tool to minimize damage to the push pins and the parts they hold together. Use the tool to first release the center pin, then pull out the body with your fingers. If the body won’t release easily, reposition the tool under the body and gently pry it out.
Step #3 – After letting the splash shield hang down, I had two additional push pins to remove (see photos below), one on each side, before I could remove the lower fascia. These were not mentioned in the Roadmaster instructions. I also did need to remove the 13mm bolt mentioned in this step.
Step 4 – I found removing a third plastic 10mm nut at the top of the wheel well made it easier to peel back the liner and access the back of the fender trim.
For this step, raising the vehicle to its maximum height with the air suspension helps with access, do this before you start the project. Turning the wheels to one side may also help with access, but avoid starting the car after disconnecting the wiring harnesses in step #5 as this may generate system errors.
Step 5 – FYI my Overland had 2 electrical harness connectors on the drivers side and 2 electrical harness connectors plus the washer hose on the passenger side. On the passenger side there was a small electrical connector with a red tab and a larger connector with a white tab. Pull back on the tab clips to be able to separate the connectors as per the videos below.
There are two more electrical connectors on the passenger side, one is a coax style connector for the radar, the other is similar to the connectors on the driver side. See the photo below.
The washer hose has an oval shaped connector, squeeze the wider parts of the oval to release it as per the video below.
To keep the washer hose from draining washer fluid, I used a fuel line clamp as shown below, but a small vise grip or anything that can gently pinch the line will do the job.
Step 6 – You can release the “arrowhead” clips by reaching behind the fender and squeezing them. That’s tough on the fingers, for a tip that may help see the video below.
Note that there are also greenish colored spring clips holding the fender trim in place so a bit of force is needed initially to get it started.
Step 7 – At this point all the connectors have been separated and all the fasteners have been removed, and the fascia is ready to come off. Watch the video below for one last tip that should make this step go smoothly.
Congratulations! The worst is over! To reassemble the fascia, just follow the steps above in reverse order.
Roadmaster 521485-5 Baseplate Installation Notes:
At this point the fascia is removed and the baseplate installation can begin. If you are installing a Roadmaster baseplate on a GC-L Overland, the following tips should be of value and may even be helpful if you are installing a different baseplate.
Note: since I did my installation of Roadmaster Baseplate model 521458-5, they have made changes to the design that now permit retention of the tow hooks (and requires drilling and cutting). I will comment below on a few of the steps where I think my experience might still be relevant.
Step 9 – I recommend saving the bumper core and related parts in case you ever want to remove the baseplate and restore the vehicle to factory condition. This will net you a better resale value in most instances.
Step 10 – I cut the air dam as described which made installation of the crossbar much easier, however I did not discard it and after all the base plate bolts were tightened, I reinstalled it by cutting clearance holes for the lower bracket bolts as show below. I’m not sure if this will still work for the newer version that retains the tow hooks.
Step 12 – there is no need to relocate the ambient temp sensor, at least that was the case on my vehicle. See step 13 for details.
Step 13 – There was no need to cut and remove the entire air dam section as shown. Initially I just cut small slits with a box cutter to fit over the upper wings of the crossbar (first 4 photos below), but later found even those were unnecessary as I had to lower the crossbar as far as it would go so it would fit thru the grill insert.
After lowering the center crossbar as far as it would go (so it would line up with the fascia grill properly) there was no need to even cut the slits in the air dam at all, as shown in the two photos below.
Step 22 – As stated in the note for this step, additional trimming of the fascia was required, there was absolutely no way it was going to fit otherwise. See photos below for where I needed to trim, photos show after trimming was completed. For this trimming process, I was able to get a neat and clean cut using an oscillating multi-tool.
To mount my air line fitting and breakaway switch I used a piece of 1″ x 1/8″ aluminum angle and attached it to the electrical connector struts using 5/16″ stainless cable clamps bought at Home Depot (see photos below). This worked out beautifully and allows up and down adjustment to suit. The fittings can be adjusted inboard or outboard on the aluminum angle to accommodate vehicles with or without a front license plate (In my case FL registrations do not require a front plate).
In the above shown version, the angle bar is mounted in front of the struts which allowed my air fitting to protrude slightly past the grill opening. This may be preferred for most people but I wanted it recessed, so later modified it so the angle bar is mounted behind the struts which fully recesses the air fitting as shown below. I will be trimming the original grill piece so it covers this area when not towing, probably using some kind of snap fitting or magnets to hold it in place. The breakaway switch swings to the side and is fully recessed in either version. I have been living with this setup now for about 4000 miles of towing and it works out perfectly.
Note: I am now considering lowering my air line and breakaway into the grill section where the electrical connector is currently located. When I upgrade my baseplate to the version that retains the tow hooks I will possibly make this change.
Demco Air Force One Installation Notes:
Following are a few photos and notes on my Air Force One (AFO) installation. I elected to install the AFO main unit under the hood on the drivers side, but it could be installed anywhere you find convenient.
As shown below, I just let the front bracket of the AFO unit rest on the substrate towards the front of the Jeep. Note: the plastic trim covers have been removed in the photos.
On the rear of the AFO unit I drilled and tapped threads in the aluminum frame bar on the Jeep and added some spacers to keep it level. The screws and washers are stainless.
Note my Toad Charge mounted to the right in the photo below – this gets raw 12v charging power thru the umbilical and provides regulated power to the Jeep battery. It also won’t let the Jeep battery flow back into the motorhome battery.
Note in the photo below the Vacuum port has been capped off with a short piece of hose and a hose plug that are included in the AFO kit. Note the Exhaust is not plugged.
No vacuum is needed on the GC-L because the brakes are electric (not vacuum boosted) and always present a soft pedal (which the AFO requires).
I ran the air line along the top of the driver side fender and into the door jamb. In the photo below these items are protected by split loom. This area will all be covered by the factory plastic trim when done.
Inside the door jamb, as shown below with the yellow arrow, I found a plastic plug, drilled a 1/4″ hole in it and fished the air line under the dash. I used a 90 degree plastic airline fitting just before entry at the plastic plug to ensure the tight bend wouldn’t crimp the airline.
Note: someone told me they found an unused rubber grommet in the firewall, but I was not able to locate it.
For the actuator I had to install the longer bolts (included in the AFO kit) to fit the wide brake pedal arm on the GC-L (in the photo below the actuator is shown with the shorter bolts).
In the photo below the red arrow points out where I installed the actuator anchor clamp to the firewall (you need to cut away the soundproofing to reach solid metal). The yellow lines are adjacent to silver sharpie markings on the brake arm where the actuator will be clamped on.
!!! USE CAUTION WHEN DRILLING INTO THE FIREWALL !!!
A reader reported using the 3 screw “Reinforcement Plate” (not shown) for the “Cable Anchor” (red arrow below) instead of the single screw needed for the Cable Anchor by itself and accidentally drove one of the three screws into a wiring harness on the engine side of the firewall. I don’t think the Reinforcement Plate is needed as the firewall is strong enough that a single screw will hold securely. Nevertheless, be VERY careful during installation.
I suggest first drilling a small diameter hole, being very careful to not to let the bit grab when it is about to punch through. Now probe thru the hole with the drill bit or a stiff wire to make sure there is nothing immediately behind. Now you can carefully enlarge the hole as necessary. I also suggest perhaps finding a screw that is just the “right” length to grab but not extend too far beyond the firewall. Another option is to use a threaded insert instead, which allows the use of a blunt ended machine screw.
Below are photos of the installed actuator.
With the trim back in place, the AFO is barely visible.
Demco AFO Brake Indicator Light Notes:
The brake indicator works via a magnet and reed switch attached to the pneumatic actuator. The purpose is to turn on an indicator light whenever the brakes are actually being applied (the pedal is physically moving). Not to be confused with activating the brake lights at the rear of the Jeep, the indicator light included in the Demco kit is intended to mount on the back of the Jeep interior rear view mirror or on the dash so you can see it in your rear camera while driving the motorhome.
Demco wants you to run the reed switch power feed wire back under the hood and tap into 12v there. IMO, it is a lot easier to just tap into 12v at the fuse panel under the dash. This eliminates running an additional wire thru thru the firewall (or door jamb) and also eliminates that awkward three way wiring crimp connector Demco wants you to use.
Below is a version of the demco wiring diagram with this modification.
To tap into the fuse panel is fairly simple using an Add-a-Circuit Fuse Tap. Jeep uses the Micro2 fuse format for the GC-L so make sure to purchase the correct version. The below photo shows where I tapped into a 5A fuse for constant 12 volt power at the fuse panel under the dash. For my dash cam, I also tapped into +12v ignition (switched) power but that is not needed for the AFO install.
Note: Be sure to follow the instructions provided with the Add-a-Circuit to ensure you have it installed correctly. If you install it backwards the power will feed thru the factory fuse before it feeds thru the new fuse, which will work, but is not proper.
Note: If you don’t like the idea of looking at your rear camera to see if the brakes are activating, alternately you can take the output of the reed switch (blue wire), run it to the umbilical connector on the front of the Jeep, and then on to the motorhome dash and install an LED indicator there.
Many motorhomes have a factory wired connection from the dash area to the 7 pin connector at the rear, intended to be use for a “Brake Controller”. Since the AFO is air powered and there is no electrical brake controller, this wire remains unused and can be repurposed for an indicator light. This is the indicator light I used. The photo below shows where I mounted it.
Demco AFO Breakaway Switch and Toad Charge Wiring Notes:
The 12 volt electrical connection for the breakaway switch (orange wire) was made at the remote battery terminals adjacent to the fuse box under the hood. This same connection is also used for the output from my Toad Charge battery maintainer. The wire to the Toad Charge should be 14 gauge or thicker. Note the Fuse (15A) which protects both the Toad Charge and the breakaway circuits.
Note: Should you ever lose the pin for your breakaway switch, you can pull this fuse to release the brakes on the Jeep.
Electrical wiring tips for the umbilical connector:
Based on experience, I know the wire terminals on the back of the tow vehicle 6-pin umbilical connector are subject to corrosion no matter how securely you tape it up – in fact, I think the tape can make it worse by retaining corrosive moisture. This time I used flowable silicone in an attempt to fully seal these connections. Time will tell.
I made the electrical connections, then wrapped a piece of clear packing tape around the body to act as a form and squeezed in the flowable silicon. Tap the assembly and/or use a toothpick to release any air bubbles.
The umbilical connector looks like it would not fit thru the Jeep grill opening, so I also installed a weatherproof six pin Deutsch connector to make it simple to remove the fascia in the future with no need to cut any wiring.
All splices are done with heat shrink butt crimps. Splices shown before shrinking with a heat gun.
Issues with Flat Towing the 2021+ GC-L:
As of the date of this post there are three so far unresolved issues with flat towing this vehicle, one potentially serious.
- After towing and coming out of Transfer Case neutral, all systems report errors. Suspension, TPMS, all the driver assist features, etc. See my video below at the 14:30 minute mark for an example. After driving the vehicle for a short distance everything clears up. Personally I consider this just an annoyance and not a serious problem – Jeep is supposedly looking into it.
- Some have found getting the vehicle out of Transfer Case neutral to be problematic, it will usually cause an error on the first several attempts. However, I have found it is probably just a matter of being patient and simply waiting 1-2 minutes (after starting the engine) before the attempt and that resolves the issue. I have heard from friends with older Jeeps and even other brands, that they have the same issue, so apparently this is not uncommon. I suggest when preparing to un-hitch, first start the Jeep, then go do something else like unhooking your towbar. When you come back a few minutes later, the transfer will usually work on the first try.
- Electronic Park Brake (EPB) activates unexpectedly – this is the serious one. I know of two GC-L owners that have dragged their vehicle and destroyed their rear tires. I have been experimenting and believe it may be a combination of Jeeps enthusiastic safety protocols combined with operator error. The GC-L has a “feature” called Automatic Park Brake (ABP). APB can be disabled, however it is never really fully disabled, a sub-feature called “Safe Hold” appears to be always active. Certain conditions will cause the park brake to apply itself, including having the door ajar or not having the vehicle in Park when turning off the ignition. Jeep supposedly has a case open to investigate the issue where the EPB engaged while towing. Fortunately in several thousands of miles and many, many tow sessions this has not happened to me by following the setup procedure described in the video below.
Notes Regarding Flat Towing the 2021+ GC-L:
- The brakes are electric and do not use a vacuum booster. A soft pedal is active when the vehicle is in tow mode (transfer case in neutral, ignition off). Actually I believe the soft pedal is always active. Supplemental braking systems need to provide light forces only, suitable for a soft pedal.
- In tow mode, the brake pedal when depressed activates the brake lights so no coach to towed vehicle wiring is needed for the brake lights.
- The steering is electric and is active while in tow mode. It is believed this keeps Jeeps “anti-death-wobble” algorithms active to prevent that problem. So far I have not experienced any hint of death wobble nor do I know of anyone else with a GC-L that has.
- Electric brakes and active steering consume a lot of power so a means of keeping the Jeep battery charged via the umbilical connector is recommended.
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