bing tracking image
  1. Tow Bar Base Plate
  2. Roadmaster
  3. Removable Draw Bars
  4. Twist Lock Attachment
  5. Partially Hidden
THIS ITEM IS NOT A FIT FOR
2026 Chevrolet Colorado
etrailer Installation
We'll connect you with nearby partnered installers who know this exact setup.
Roadmaster

Roadmaster Crossbar-Style Base Plate Kit - Removable Arms

Part Number: RM-521423-4
In Stock
$575.00
Retail:$932.23
You Save: $357.23
Tow Bar Base Plate
Not Confirmed to Fit

2026 Chevrolet Colorado

Will this fit?

To see if this custom-fit item will work for you please tell us what vehicle you'll use it with.

zoom in icon
slider vertical icon
zoom out icon
Comment field cannot be left empty.
Name field cannot be left empty.
By submitting this form, you understand and agree to our Terms of Sale, Website Terms of Use and Privacy Policy.

Thank you! Your comment has been submitted successfully. You should be able to view your question/comment here within a few days.

Error submitting comment. Please try again momentarily.

Product Images

Customer Photos

etrailer Installation
We'll connect you with nearby partnered installers who know this exact setup.
Roadmaster's crossbar-style brackets are virtually invisible, easy to mount and simple to remove. Brackets install on your vehicle's frame to provide attachment points for your tow bar. Great Prices for the best tow bar base plate from Roadmaster. Roadmaster Crossbar-Style Base Plate Kit - Removable Arms part number RM-521423-4 can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
  • All Info
  • Reviews (2209)
  • Q & A (0)
  • Photos

Roadmaster Tow Bar Base Plate - RM-521423-4

Highlights

  • Custom Fit for Your Vehicle: Mounts to existing attachment points
  • Ready for Flat Towing: Installs on the frame to create strong attachment points for your tow bar.
  • Blends In When Not Towing: Hidden bracket design keeps the front end looking clean when arms are removed.
  • Quick to Connect or Remove: Twist-lock drawbars click in place and release with built-in pull rings.
  • Built to Last: Computer-cut, all-steel construction with black powder coat resists corrosion and wear.
  • Simplifies Setup: Integrated mounts make it easy to add an electrical connector plug or bracket.
Made in USA

Features to know about

Made for a Clean Front End: Hidden Design with Removable Drawbars

If you like your vehicle to look untouched when not towing, this setup keeps it that way. The hidden bracket design keeps the mounting points tucked far back, leaving only a clean grille line once the arms are removed. The partially hidden brackets stay protected from scrapes and scuffs, keeping the front end neat and free of bulky hardware.

Hooks Up Fast: Twist-Lock Arms with Built-In Pull Rings

Getting connected doesn’t take much effort here. The removable drawbars slide into the brackets, click to lock in place, and release with a twist using the built-in pull rings. No tools or pins to fumble with—just twist, lock, and go. When unhooked, you twist again to pull them free and you’re left with nothing visible up front.

Built to Last: All-Steel Construction with Black Powder Coat

The computer-cut, all-steel build is designed for strength and durability through countless miles of towing. The black powder coat finish protects against corrosion and road wear. It bolts directly to the frame with no welding required, spreading towing forces evenly for a solid, reliable connection every time you tow.

Keeps Your Setup Organized: Integrated Mounting Points for Wiring

You can mount an electrical connector plug or bracket (sold separately) directly on the base plate using the integrated mounting points. That means your wiring stays tidy and within reach when hooking up your tow bar, keeping your setup clean and ready for the next trip.

Compatible with Roadmaster Tow Bars Using a Crossbar

Already have a Roadmaster tow bar? This base plate works with them when paired with the quick-disconnect crossbar (910021-00, sold separately). It’s an easy way to keep your existing towing gear in play while adding the clean design and quick-release features of this kit.

Specs

Features

  • Hidden bracket design: Provides improved aesthetics compared with standard brackets
  • Crossbar-style brackets: Sit far back for a supremely clean look
  • Drawbars: Attach and remove quickly and easily
  • Arms: Click to lock in place in brackets
  • Built-in pull rings: Let you unlock arms so you can twist and remove them
  • Computer-cut, all-steel construction: Provides exceptional strength
  • Black powder coat finish: Durable and corrosion resistant
  • Simple installation: No welding required
  • Custom base plates: Ensure a perfect fit for your vehicle
  • Integrated mounting points: Let you easily attach an electrical connector plug or bracket (sold separately)
  • Compatibility: Compatible with Roadmaster tow bars with use of quick-disconnect crossbar (910021-00 - sold separately)
  • Instructions and mounting hardware: Included
  • Manufacture location: Made in the USA
  • Warranty: Limited Lifetime Warranty

Design Details

  • Base Plate Style: Crossbar-Style
  • Arm Type: Removable Arms with Twist Lock Attachment
  • Visibility: Partially Hidden Installation
  • Construction Material: All-Steel, Computer-Cut Components
  • Finish: Black Powder Coat – Corrosion Resistant

Compatibility

  • Tow Bar Compatibility: Compatible with Roadmaster tow bars when used with quick-disconnect crossbar (910021-00 – sold separately)
  • Vehicle Fitment: Custom base plates ensure a perfect vehicle-specific fit (refer to manufacturer application guide)

Included Components

  • Contents: Base plate kit, instructions, and mounting hardware

Warranty and Origin

  • Warranty: Limited Lifetime Warranty
  • Country of Manufacture: Made in the USA

521423-4 Road Master EZ4 Base Plate Kit

Replaces 521423-1

Installation Details RM-521423-4 Installation instructions

This Product Fits The Following Vehicles




Customer Satisfaction Score:

Ratings & Reviews

4.8

2209 reviews
5 Stars
(1862)
4 Stars
(261)
3 Stars
(48)
2 Stars
(13)
1 Star
(25)
Review sort icon
Roadmaster's crossbar-style brackets are virtually invisible, easy to mount and simple to remove. Brackets install on your vehicle's frame to provide attachment points for your tow bar.

by:



by:



by:



by:

Went in Smoothy



by:

Great service and quick delivery. Always have what I need.



by:

Very pleased in the condition of our packages when they arrived and how timely they arrived.



by:

easy to install/



by:

As always very best service and know what they talking about!!!



by:

Fit perfectly



by:

So far everything is good



by:

Works great. Easy operation.



by:

Easy instillation have used product a lot with no proplems



by:

Was easy to install and use . We have used them several time in the last year .



by:

Britney was great to deal with. etrailer and the staff have always been great! I will return.



by:

Easy installation, has worked well for me. Would purchase again if I change toads.



by:

Easy to install and use, no complaints at all I will definitely be shopping at Etrailer again



by:

I love it. I watched the how to install video on your web and the instructions were easy to follow. Didn’t take long.



by:

Over all a very well made base plate the only issue I had was the front bolt on both of them it would go up into the plate and you can not get to it with a wrench or a socket I had to drive a large screwdriver beside it to hold the bolt and run the nut down with a wrench



by:

Very well made. Installation went just as stated in the instructions!



by:

Exactly what I needed when I really didn’t know what I needed. Erica was the rep that helped me get the right parts I needed for my Jeep.
Thanks Erica.

Richard profile picture

Richard

3/28/2019

Works like a charm. We have had no problems with the plates. Very pleased with the product. Well worth the money.



by:

I installed the base plate system on my 2007 Jeep Liberty. I cheated for comfort by putting the Jeep on my 12000lb hoist. Depending on what task I was dewing, I could sit on my stool and move the hoist up or down. This way I could stand or sit to work. I kept the directions close at hand and when I ate my lunch, I watched [online] for hints. I had no problems with my install. The shops wanted over $xxx to do the work. I would have had to wait about 6hrs at the shop. I spent about 7 hrs working at home, but not working hard. Happy Camper.



by:

Good instructions fairly easy to install



by:

Received package and made the repairs took UPS forever not ETrailers fault I had to buy entire installation kit as couldn’t get just the parts needed in a timely manner so cost twice as much and I have extra parts I don’t need but I am back on the road thank you



by:

Very Happy! The shipping was fast; 3 days, including Thanks Giving. I was able to instal the base plat myself, just following the installation video on their web site. I watched it a couple of times while I was waiting for delivery, and then followed it step by step during installation. I wouldn't have dared attempt it myself without the video. I also installed the Tail Light Wiring Kit with Bulbs-RM-155 using the same method. Everything went without a problem. I will be buying from eTrailer again.



by:

The Base plate kit is well made and came with all the necessary hardware.Installation is relatively straight forward. I did have to enlarge two of the holes that didn't quite line up. But overall I'd recommend it.

David profile picture

David

5/24/2026

It continues to work flawlessly


25
25

See what our Experts say about this Roadmaster Tow Bar Base Plate

  • Parts Needed to Flat Tow 2003 Jeep Liberty With Roadmaster StowMaster
    The Roadmaster StowMaster # RM-501 requires crossbar-style base plates. A complete setup for your 2003 Jeep Liberty will require a base plate kit, tow bar wiring, and a supplemental braking system. I'm not entirely sure what you own beyond the tow bar and the safety cables so I apologize if I'm listing something you already have. I recommend the following: -Roadmaster Crossbar-Style Base Plate Kit - Removable Arms # RM-521423-4. -Roadmaster Diode 7-Wire to 4-Wire Flexo-Coil Wiring Kit...
    view full answer...
  • Can I Purchase Replacement Removable Arms for the Roadmaster Base Plate Kit?
    You may purchase replacement drawbars for the Roadmaster EZ kits. Each base plate has its own specific draw bars that you must use. They are of a specific shape and design to be used on a specific vehicle so you cannot interchange them. For replacements for base plates you will need # RM-ARMS. Use the instructions, linked to the right, which is actually a form that needs to be filled out to ensure the new replacement arms will fit. If you need replacements for the 2005 Jeep Liberty, the...
    view full answer...
  • What Is The Hardware Kit I Need For A Roadmaster Crossbar-Style Base Plate Kit, Part # 521423-4
    The hardware kit that you need for the Roadmaster Crossbar-Style Base Plate Kit, part # RM-521423-4, is the Replacement Hardware Kit for Roadmaster Crossbar-Style Base Plate Kit, part # RM42ZR. This crossbar type base plate fits your 2005 Jeep Liberty. I have included a product description link below.
    view full answer...
  • Parts Needed to Flat Tow a 2007 Jeep Liberty Behind an RV
    There are several differences between the EZ5 base plates # RM-521423-5 and the regular EZ base plates # 521433-1. The biggest difference is what each of them fits. EZ5 base plates # RM-521423-5 fit the 2002 to 2007 Jeep Liberty. EZ base plates # 521433-1 fit the 2008 to 2012 Jeep Liberty. Since you have a 2007 Liberty you would need to use either the EZ5 base plates # RM-521423-5 or the EZ4 base plates # RM-521423-4. The difference between these is the design of the removable arms. There...
    view full answer...
  • Roadmaster Explorer Tow Bar And Roadmaster Base Plate Compatibility
    The Roadmaster Explorer Tow Bar you have is the previous version of the StowMaster # RM-501 and has a weight rating of 5,000lbs. You need the Roadmaster Tow Bar Quick Disconnects - Car Side Only Item # RM-222 to connect it to your base plates # RM-521423-4. Just bolt the # RM-222 to your base plates and you'll be able to connect the tow bar right to them. The video I've attached will show you exactly how to do this.
    view full answer...
  • Parts Needed to Flat Tow a 2006 Jeep Liberty
    Unfortunately, the baseplates from your friend's CJ5 are likely not going to work. I can't say for certain since I don't know what they are but there are no base plates that we carry that will fit a CJ5 and your 2006 Jeep Liberty. We also do not have a list of installers around the country so there isn't a specific location I can refer you to. All the necessary parts to set your Jeep up to flat tow can be installed by a common mechanic so you may want to look around at shops that might...
    view full answer...
  • Recommendation for Parts Needed to Flat Tow a 2007 Jeep Liberty
    You are correct. For your 2007 Jeep Liberty, you will need base plates to flat tow it. You can use the EZ4 Style Base Plates, # RM-521423-4. I have included a link to a video showing a typical installation. If you would like to use the Tow Ready Tow Bar, # 63180, you will need to use an adapter, # RM-025, and Quick Disconnects, # RM-201, to adapt the tow bar to the base plates. You will also need to Keep in mind that this tow bar is rated for towing speeds of 45 miles per hour or less....
    view full answer...
  • Adapter Needed for the Reese Tow Champ Tow Bar to RoadMaster Base Plates for the 2006 Jeep Liberty
    Yes, there is an adapter for you Reese Tow Champ Tow Bar, part 74950. It is the Roadmaster Base Plate to Tow Ready Tow Bar Adapter, item # RM-025. This adapter will connect to your tow bar and allow you to connect to the Roadmaster # RM-521423-4 Base Plate Kit, that you are installing on your Liberty. Along with this adapter you will need the Roadmaster Tow Bar Quick Disconnect Kit, item # RM-201 to easily remove the adapter and tow bar from the towed vehicle. You will get the short safety...
    view full answer...
  • Parts Needed to Flat Tow a 2006 Jeep Liberty with a Roadmaster Sterling All-Terrain Tow Bar
    According to the owner's manual I found online your 2006 Jeep Liberty can be flat towed since it has 4-wheel drive. You should verify with your printed copy if you haven't already. The base plates to use with your Sterling All-Terrain Tow Bar # RM-576 is the EZ4 Kit # RM-521423-4. These are custom fit for the Liberty. For safety cables us # RM-643. In addition to the tow bar and base plates you'll need wiring to power the Jeep's lights, a braking system, and likely a high-low adapter. To...
    view full answer...
  • Can I Install Baseplates without Removing the Bumper of my 2002 Jeep Liberty 3.7 Renegade?
    Hey Mich! Looking at the installation instructions for the Blue Ox Base Plate Kit # BX1119 and your 2002 Jeep Liberty 3.7L Renegade, the bumper will need to come off for the installation, even though you have tow hooks installed already. There are some frame attachments that require removal during the installation, which is why the bumper will be removed. Looking at other baseplate styles for the 2002 Liberty such as the Roadmaster Crossbar-Style Base Plate Kit # RM-521423-4, it looks...
    view full answer...
  • Needed Tow Bar and Accessories to Flat Tow 2007 Jeep Liberty
    In order to flat tow your Liberty, you will need to install a base plate kit. I would recommend the Roadmaster EZ4 Base Plate Kit, part # RM-521423-4. A base plate offers a safe and secure attachment point to the vehicle. This particular Roadmaster kit offers easily-removable drawbars. One they are removed, the bracketry is pretty much invisible. If you are mechanically inclined, you might be able to handle the installation, but it is fairly involved. Typically, an RV would have a receiver...
    view full answer...
  • Is there an Adapter to use Roadmaster StowMaster Tow Bar with Blue Ox Base Plates on a Jeep Liberty
    We have several adapters that can be used with Blue Ox base plates and other tow bar systems. Unfortunately we do not currently offer an adapter that will work for with your StowMaster 5000 tow bar that will be compatible with the Blue Ox base plate kit, # BX1122, that you have ordered. I have included a helpful article that shows base plate and tow bar adapters and compatibility. You can either use a different set of base plates like the Roadmaster # RM-521423-4. Or you could use a...
    view full answer...
  • Recommended Flat Towing Setup for a 2005 Jeep Liberty With Roadmaster EZ4 Base PLate Kit
    I really like the base plate kits that have the removable arms like the Roadmaster EZ4 # RM-521423-4 does because it will give your vehicle, your 2005 Jeep Liberty in this instance, much more of an OEM look when you are not flat towing it. I do not recommend using the Tow Ready Adjustable Tow Bar # 63180 as it is a very entry-level tow bar that requires the tow bar mounting brackets to be bolted to your bumper. For some applications there will need to be a custom bracket installed due...
    view full answer...
  • Is Install of Base Plate Kits for 2002 Jeep Liberty Difficult
    The Roadmaster StowMaster part # RM-501 can be used to tow your 2002 Jeep Liberty but it will require you to install a base plate kit too with the part # 521426-1 if you have a brush guard or part # RM-521423-4 if you do not have one. The install of these kits isn't exactly difficult but it can take some time so you'd just need to set aside enough time and it would be very easy overall.
    view full answer...
  • Recommended Dinghy Towing System for 2006 Jeep Liberty
    I'm happy to assist with recommendations for your 2006 Jeep Liberty for flat towing. Your Roadmaster tow bar will work just fine with the Roadmaster Crossbar-Style Base Plate Kit # RM-521423-4 and Loctite # LT37420. Then you will also need the safety cable # RM-643. Then for your tow bar wiring, I recommend the Hopkins Custom Tail Light Wiring Kit for Towed Vehicles # HM56203 along with the Hopkins Nite-Glow Tow Bar Extension Cord w/ Socket - Coiled - 7-Way RV to 6-Way Round - 8' Long...
    view full answer...
    Image 1 for
  • Recommended Components for Flat Towing 2002 Jeep Liberty Behind a Motor Home
    The Roadmaster EZ4 Base Plate Kit # RM-521423-4 is a good fit for your 2002 Jeep Liberty as long as your vehicle does not have a brush guard. This kit features a hidden bracket design which allows the draw bars to be easily removed via 2 pins, giving the base plates a more subtle appearance. It is also compatible with all Roadmaster tow bars. If your Jeep does have a brushguard, you can go with the Roadmaster EZ Base Plate Kit # 521426-1. Prior to flat towing your vehicle, be sure to...
    view full answer...
  • Can EZ5 Base Plates Be Used With Roadmaster Stowmaster Tow Bar On 2005 Jeep Liberty
    The base plates that are designed to fit your 2005 Liberty and work with your Stowmaster tow bar are part # RM-521423-4. These are the EZ4 base plates, and have removable arms so it gives your Jeep a nice clean look when they are removed. The EZ5 base plates, part # RM-521423-5, will not work with any tow bars that use a hitch ball and are designed to work with tow bars that slide into a trailer hitch. For tow bar lighting I recommend the Hopkins Custom Wiring, part # HM56203. To...
    view full answer...
  • Will the Roadmaster Falcon All Terrain Part # RM-522 Fit a 2007 Jeep Liberty
    Roadmaster currently has two base plate kits for your 2007 Jeep Liberty which are the Roadmaster EZ5 Base Plate Kit part # RM-521423-5 and the Roadmaster EZ4 Base Plate Kit part # RM-521423-4. Both the EZ4 and EZ5 will work with the Roadmaster Falcon All Terrain part # RM-522. You will not need any additional parts to pair the Falcon with the EZ4/EZ5 base plates. I have attached a review video of the tow bar for you as well. If you need any other parts to complete your flat-towing setup...
    view full answer...
  • Does Steering Wheel of 2006 Jeep Liberty Need to be Unlocked to Flat Tow it
    When flat towing your 2006 Jeep Liberty with a base plate kit like the Roadmaster part # RM-521423-4 that you referenced if you follow the flat towing procedure that's outlined in the owners manual the steering wheel would be unlocked like it would need to be.
    view full answer...
  • Availability of Plug and Play Flat Towing Wiring Harness/Flat Towing Equipment for 2004 Jeep Liberty
    I believe TowDaddy was purchased by Hopkins a couple few years ago. Hopkins offer a plug and play flat towing wiring harness, part # HM56203. If you click the provided link, you can see an installation video showing the harness being installed on a 2006 Jeep Liberty. To fully equip your Liberty, you'll need base plates, a tow bar, safety cables, the wiring solution you've asked about, a supplemental braking system and perhaps a high/low adapter to level the tow bar. For base plates, I'd...
    view full answer...
  • Base Plate Kit, Tow Bar, Safety Cables, and Lighting Needed to Tow 2004 Jeep Wrangler
    In order to use a tow bar with your Jeep, you will need to add base plates, # RM-521423-4 for models without brush guard or # 521426-1 for models with brush guard. You will then need to add Roadmaster Base Plate to Tow Ready Tow Bar Adapter, # RM-025, to be able to use the Tow Ready Tow Bar, # 63180. Keep in mind that this tow bar is rated for towing speeds of 45 miles per hour or less. The RoadMaster Tracker Tow Bar, # RM-020, may be a much better choice if you will be towing often or...
    view full answer...
  • How to Order Replacement Arms for Roadmaster Base Plate Kit
    If you were to lose one of the arms that came with the base plate kit part # RM-521423-4 (or any Roadmaster kit) you'd have to order the replacement arm kit part # RM-ARMS which actually is a request sent off to Roadmaster to have a custom arm made since they are all unique to the vehicles they fit. Due to some variances sometimes two different identical part number base plate kits won't allow the arms of the other to fit.
    view full answer...
  • Roadmaster Stowmaster Tow Bar-Compatible Base Plates for 2002 Jeep Liberty
    To use your Roadmaster # RM-501 Stowmaster with your 2002 Jeep Liberty, you'll need to use a crossbar-compatible base plate kit. If your Liberty has a brush guard, you'd use # 521426-1, or # RM-521423-4 for Liberty models without a brush guard. You'll also need safety cables like # RM-643, a wiring solution like # RM-15267, and a supplemental braking system like # SM99251 if the motorhome has hydraulic brakes or # SM99243 for motorhomes with air brakes. You'll also need the # RM-88400...
    view full answer...
  • Compatiblility of Blue Ox Patriot Brake System With 2006 Jeep Liberty
    I've confirmed with Blue Ox that the # BRK2012 Patriot II supplemental braking system is indeed comaptible with your 2006 Jeep Liberty. If you aren't already equipped with them, you'll need some additional items to complete your flat towing system. For a tow bar, I'd recommend the Falcon All Terrain tow bar, part # RM-522. The Falcon features non binding, self centering arms, which allow you to hook up to the motorhome even if the terrain isn't completely level or the tow vehicle isn't...
    view full answer...


< Previous
12



Do you have a question about this Tow Bar Base Plate?


Info for this part was:

Employee Mike L
Expert Research:
Mike L
Employee Michael H
Expert Research:
Michael H
Employee Jameson C
Expert Research:
Jameson C
Employee Jeffrey L
Expert Research:
Jeffrey L
Employee Shelly K
Updated by:
Shelly K
Employee Jenny M
Updated by:
Jenny M
Employee Mike S
Updated by:
Mike S
Employee Isabelle B
Updated by:
Isabelle B
Employee Wilson B
Written by:
Wilson B

At etrailer we provide the best information available about the products we sell. We take the quality of our information seriously so that you can get the right part the first time. Let us know if anything is missing or if you have any questions.