1. Tow Bar
  2. Roadmaster
  3. Fits Roadmaster Base Plates - Crossbar
  4. Coupler Style
  5. Telescoping
  6. 6000 lbs
Roadmaster StowMaster Tow Bar - Car Mount - 2-5/16" Ball - 6,000 lbs

Roadmaster StowMaster Tow Bar - Car Mount - 2-5/16" Ball - 6,000 lbs

Item # RM-504
lowest price pledge
Retail:$830.14
Our Price: $729.96
You Save: $100.18
Tow Bar
This item qualifies for Free Shipping
Shipping Weight: 60 lbs
Quantity: 
Tow Bar RM-504 - Fits Roadmaster Base Plates - Crossbar - Roadmaster
zoom in icon
slider vertical icon
zoom out icon
Comment field cannot be left empty.
Name field cannot be left empty.

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

Videos

Product Expert Kristina F

Is this right for you? Product Expert Kristina F says:

Yes, if you:

  • Tow a Jeep, sedan, or mid-size truck
  • Worry about how your car might track behind your RV during turns and need a better turning radius
  • Want to use your 2-5/16" tow ball to tow your car instead of your receiver

No, if you:

  • Tow a larger vehicle or SUV - your loaded down vehicle may exceed the 6,000-lb weight rating
  • Don’t want to have to drive your car around with your tow bar folded up on the front
Tow bar with 2-5/16" coupler has stainless steel, telescoping arms that automatically lock. Its large hookup radius allows you to connect without perfectly lining up your vehicle. Quick-disconnects make it easy to attach to base plates. Lowest Prices for the best tow bar from Roadmaster. Roadmaster StowMaster Tow Bar - Car Mount - 2-5/16" Ball - 6,000 lbs part number RM-504 can be ordered online at etrailer.com or call 800-298-1624 for expert service.
  • All Info
  • Reviews (56)
  • Q & A (13)
  • Photos
  • Why etrailer?

Roadmaster Tow Bar - RM-504

  • Fits Roadmaster Base Plates - Crossbar
  • Coupler Style
  • Roadmaster
  • Telescoping
  • 6000 lbs
  • Standard
  • Steel
  • Stores on Car

Tow bar with 2-5/16" coupler has stainless steel, telescoping arms that automatically lock. Its large hookup radius allows you to connect without perfectly lining up your vehicle. Quick-disconnects make it easy to attach to base plates.


Features:

  • Tow bar lets you tow your vehicle safely and securely behind your motorhome
  • Large hookup radius makes connecting a breeze at any angle, even if your vehicle isn't perfectly lined up with your RV
  • Quick-disconnect system lets you quickly and easily mount the tow bar on your towed car
    • Quick-disconnect brackets on tow bar match up with brackets on base plates and are held in place with sturdy pins
  • Self-aligning design - just hook up and drive RV forward
    • Arms extend into rigid, tow-ready position and automatically lock in place
  • Extra-long telescoping arms allow for better maneuverability and easier towing
    • Stainless steel construction of inner arms allows for smooth operation
    • Safety straps inside each arm provide extra security in case the latches malfunction
  • Full-length crossbar with angle iron brace provides maximum strength and support
  • Strong, corrosion-resistant tow bar is built to last
    • FEA testing guarantees a strong finished product
    • Self-lubricated nylon bushings eliminate friction between the inner and outer arms for a longer-lasting, better-functioning system
    • Welded steel plugs seal the ends of the tow bar to guard internal components
    • High-tech powder coat finish provides additional durability
  • Simple, secure storage alongside vehicle
    • Just fold up the tow bar and secure it using the collar under the coupler
  • Made in the USA


Specs:

  • Compatibility: works with most Roadmaster EZ, EZ2, EZ4, XL, and Classic vehicle-specific base plates
    • Will not work with MX, MS, or EZ5 base plates
  • Ball diameter: 2-5/16"
  • Weight capacity: 6,000 lbs
  • Limited lifetime warranty


Necessities for Flat Towing

For the RVFor the Towed CarTo Link the Towed Car and RV
HitchBase platesTow bar
Wiring plugBraking systemSafety cables
Wiring kit/diodesWiring adapter cord

Quick, Easy Hookup

This Roadmaster tow bar has a large hookup radius to ensure simple, secure hookup. What this means is that, even if your towed car is not perfectly aligned with your RV, you will still be able to make the necessary connections. To achieve this, the StowMaster has stainless steel, telescopic inner arms that adjust independently. In addition, 1 of these arms is able to pivot in and out, changing the spread. So, if your car is angled a bit behind your RV, you'll still be able to hook up by bringing the arms closer together and staggering the length so that 1 arm is longer than the other, allowing it to reach the more distant base plate.


The fact that the arms are extra-long also allows for a better turning radius. By putting more distance between your motorhome and your towed car, your entire setup will become easier to maneuver so that your towed car will track behind your motorhome without running the risk of hitting your RV during turns.


Autowlok

The Autowlok mechanism features a spring-loaded pin that locks the telescoping arms into place for towing. Once the tow bar is connected to both your RV and to the base plates on your towed vehicle, simply drive the RV forward until the tow bar arms fully extend, at which point they will automatically lock into place.


Once you've reached your destination and you're ready to unhook your vehicle, press the release button to disengage the spring-loaded pin. The arms will be able to telescope again, making it easier to disconnect. However, if you're on uneven terrain, or if your towed vehicle is not perfectly aligned behind your RV, chances are you'll experience tow bar binding. This is the result of tension that can build up in the telescoping arm, and it can make it difficult to disconnect your vehicle. Using a release tool (RM-066 - sold separately) will give you the leverage necessary to disconnect.


The internal self-lubricating nylon bushings help to absorb road shock and reduce wear and tear on the tow bar by eliminating friction between the inner and outer arms as they telescope in and out. Inside each arm, a built-in safety strap provides extra peace of mind by ensuring that the inner and outer arms won't separate in the event of a latch failure.


Quick-Disconnects

Quick-Disconnect

Standard on most Roadmaster tow bars, quick-disconnects make it a snap to attach the tow bar to your vehicle. Other methods require you to maneuver each tow bar arm individually and perfectly line up tabs on the arms with tabs on your base plates. Roadmaster's unique design lets you connect and disconnect the tow bar quickly and easily, all by yourself.


The quick-disconnect brackets come in separate pieces. The pieces that are positioned on the ends of each tow bar arm interlock with matching brackets that attach to your Roadmaster base plates. Sandwiched between the tow bar arms is a sturdy crossbar that essentially turns the arms into a single structure. This crossbar allows you to lower the tow bar as a single piece onto the quick-disconnect brackets on your towed car so that you don't have to connect each arm separately. When lowering the tow bar onto the brackets, make sure that the tab on each bracket lines up with the hole in the matching bracket. Then just insert the linch pins through the holes in the tabs on top to secure the brackets together. To remove the tow bar, simply remove the pins and lift the tow bar off of the brackets. These convenient brackets also make it simple to mount any number of Roadmaster accessories, from basic safety cables to the Guardian rock shield.


Superior Testing Ensures Excellent Quality

FEA test

This StowMaster tow bar has been subjected to rigorous physical and computerized testing to ensure that it meets Roadmaster's exceptionally high standards. Throughout the design process, Finite Elemental Analysis (FEA) is done. Each of these tests display a 3-dimensional image of the tow bar while it is put under thousands of pounds of pressure. Areas of stress in the tow bar can then be located and studied so that those areas can be strengthened. This process is repeated until any weak spots, particularly those found in load-bearing components, are completely removed. The result is a durable, strong, and safe product.


Simple Storage

FOLDED STOWMASTER

The StowMaster can easily be folded up and stored on the front of your towed vehicle when not in use. After disconnecting the tow bar from your RV, push the arms of the tow bar together so that they are side by side and fold them up towards the vehicle. There is a collar under the coupler that fits over a vertical post on the crossbar. This secures the tow bar in the stored position on the front of your car.


Guide to Flat Towing

Flat towing your vehicle is much more convenient than using a trailer or a tow dolly. These other options take up much more storage space, leaving you less room both at home and at the campsite. In addition, securing your vehicle to a trailer or tow dolly can be a hassle and more time consuming than hooking up with a tow bar.


There are 5 basic components needed when flat towing a vehicle: a tow bar, a base plate kit, a safety cable set, tow bar wiring, and a supplemental braking system.


FlatTowing Components

The tow bar links your towed car to your motorhome. It attaches to the custom-fit base plates that install on the frame of your towed car. Safety cables ensure that your towed car does not separate from your motorhome in the event that your tow bar becomes detached. Tow bar wiring allows your towed vehicle's signal lights to sync up with your motorhome's tail lights, which is required by law in most states. Finally, the supplemental braking system - also required in most states - brakes your towed car when the brakes in your motorhome are activated, preventing wear on the motorhome and decreasing braking distance for your entire setup.



504 Road Master Stow Master Coupler-Style Tow Bar for 2-5/16" Hitch Ball






Customer Reviews

Roadmaster StowMaster Tow Bar - Car Mount - 2-5/16" Ball - 6,000 lbs - RM-504

Average Customer Rating:  4.9 out of 5 stars   (56 Customer Reviews)

Tow bar with 2-5/16" coupler has stainless steel, telescoping arms that automatically lock. Its large hookup radius allows you to connect without perfectly lining up your vehicle. Quick-disconnects make it easy to attach to base plates.

- RM-504
by:

Nice, solid product. Easy to install and remove. Sliding action is very smooth, easy to extend and fold. My hitch coupler is slightly different design than shown but seems very heavy duty.



- RM-504
by:

Great equipment !



- RM-501
by:

Review from a similar Stowmaster in Tow Bar


If you are thinking of towing a car this is the company to see. Just installed a base plate and tow bar to my Toyota. Took just 2 hours. With the video and instructions, no problems, very easy. Customer support excellent, very helpful. If you don’t think that you can do this install yourself, think again. I would recommend this tow bar, with the telescoping arms connecting to the car is very simple and secure. This is a 5 star product. Thank You



- RM-501
by:

Review from a similar Stowmaster in Tow Bar


The StowMaster Tow Bar works great. We used to trailer our jeep behind the motorhome, but now wouldn't do it any other way. The tow bar makes for a way better towing experience.



- RM-501
by:

Review from a similar Stowmaster in Tow Bar


It was a tough installation, but we got it installed. The tow bar works well. It takes some strength to attach to a the ball on my RV.


Comments
Only used it twice. It worked fine when I was towing a four door Jeep. Releasing the tow bar took some muscle.
BJ C - 01/11/2021


- RM-501
by:

Review from a similar Stowmaster in Tow Bar


Appears to be a high quality product, that came with good instructions, and all the parts for installation on the base plate already installed on my Honda Fit. This will allow me to flat tow the car behind my class A motor home.


Comments
The road master tow bar is still functioning properly with no issues, a safe,reliable well made product.
Frank - 07/20/2020


- RM-501
by:

Review from a similar Stowmaster in Tow Bar


This product is well made and well engineered. It performs the functions of allowing a reasonable amount of flexibility in coupler/ball alignment, locking into place, smooth vehicle towing and securing into the "stowed" position. Because of my bumper mounted winch, I needed to make some adaptations to the mounting system which the RM-501 accommodated very well. I am very pleased with this purchase. I will send a couple of installed pictures by seperate email.



- RM-501
by:

Review from a similar Stowmaster in Tow Bar


Bought this from Etrailer with all the supporting hardware needed to flat tow my Durango. The quality is excellent (stainless steel, very strong), the install was pretty easy. Only issues I had were because of the are of my vehicle. Towing with it and hooking up is simple. It takes only a minute to go from stowed to hooked up. Etrailer.com was easy to deal with, helpful, and shipping was very fast. This is my second order with them, both have been flawless. Their pricing also proved to be the lowest.



- RM-501
by:

Review from a similar Stowmaster in Tow Bar


Seems to be a good solid tow bar; no problems, easy to hook up tow vehicle by myself.



- RM-501
by:

Review from a similar Stowmaster in Tow Bar


This tow bar with the base plate and rock guard is the finest set up I have seen for towing a rig behind a RV. Combined with the patriot brake system and magnetic light system makes me ready to go in style with safety. I'm a happy boy!



- RM-501
by:

Review from a similar Stowmaster in Tow Bar


Absolutely love my Roadmaster tow bar from etrailer.com. Easy to hook up and easy to unhook, a great edition to our camping gear!!! Thanks etrailer.com great price and great service!!



- RM-501
by:

Review from a similar Stowmaster in Tow Bar


I use mine professionally to tow my jeep behind semi tractors that i deliver from the factory.



- RM-501
by:

Review from a similar Stowmaster in Tow Bar


I am pulling a Jeep behind a pickup camper so I don’t have a place to stow the tow bar like a motor home. This tow bar folds nicely and fits on the front of a Jeep well.



- RM-501
by:

Review from a similar Stowmaster in Tow Bar


Arrived on time, fit as promised, good quality parts, performs as expected. Really, what more can you ask for?



- RM-501
by:

Review from a similar Stowmaster in Tow Bar


A quality product. Very easy install Used the frame mount from the same company, same review



- RM-501
by:

Review from a similar Stowmaster in Tow Bar


Install was so easy, works great. No co mplaints.



- RM-501
by:

Review from a similar Stowmaster in Tow Bar


This is a very well made hitch. It was very easy to fit, is very robust and very easy to fold away. I bought the optional cover which makes the unit very neat when not in use.



- RM-501
by:

Review from a similar Stowmaster in Tow Bar


Love this towbar. By myself, I can hook up to my motorhome and be ready to hit the road in 10 minutes .



- RM-501
by:

Review from a similar Stowmaster in Tow Bar


I did a lot of research on what tow bar I wanted for my Jeep Wrangler and this is the perfect unit for me and what I have to tow with.



- RM-583
by:

Review from a similar Stowmaster in Tow Bar


Very satisfied with my etrailer experience William was very professional and knowledgeable I will definitely be a return customer



- RM-501
by:

Review from a similar Stowmaster in Tow Bar


Tow bar folds and fits nicely on front of car. It also fits nicely in trunk. Easy to adjust to fit ball on hitch. Good product works, well with Roadmaster EZ base plate kit with removable arms. Used to tow car behind RV.



- RM-501
by:

Review from a similar Stowmaster in Tow Bar


I bought the RM baseplate for my jeep because they may an adaptor for the Duncan tow bar. I got the Duncan on craigslist and it looked great. But I didn't know that I needed a DUNCAN quick release kit. It wasn't on it. The RM quick release only attaches the RM Duncan adaptor to the baseplate. So learn from my mistake don't buy a used Duncan unless you are sure you have all the parts. I out $200 for very nice looking hardly used but worthless Duncan tow bar plus the return shipping for the RM 038 and RM 021. The only solution to this was to buy the RM-501 tow bar which is what I should have done in the first place. It is very well made and easy to stow or remove. How much are they getting for scrap metal these days.



- RM-501
by:

Review from a similar Stowmaster in Tow Bar


I was very pleased with the products I ordered from you. I was also extremely pleased with the professionalism, informative, friendly and helpful young lady that took my order. Her name is Katie. Everyone else I dealt with was also very good and knowledgeable. My order was, Tow Bar, Base Plate, Rear Trailer Hitch, Light Bulb, Wiring Kit and other accessories. Everything fit perfectly. Thanks for all of your help.



- RM-501
by:

Review from a similar Stowmaster in Tow Bar


This is a premium quality item. Very well made from heavy materials. I'm still installing the baseplate so I haven't use the tow bar yet but as soon as I took it out of the box, there is no question it's a quality product. I'll review again after my first tow. There was a slight problem with my delivery in that I didn't receive the "vehicle side" hardware. I contacted etrailer.com and they are sending it out immediately. Really good customer service!



- RM-581
by:

Review from a similar Stowmaster in Tow Bar



30
65
Show More Reviews

Ask the Experts about this Roadmaster Tow Bar

  • Compatibility of the Adapter Brackets # BX88151 with the Roadmaster StowMaster # RM-504
    The Roadmaster StowMaster Tow Bar # RM-504 is an economy tow bar so it doesn't have the ability to adapt the arms to fit with the Blue Ox Base Plate Adapter Brackets # BX88151 but you can use the Roadmaster Falcon 2 Tow Bar # RM-520 instead.
    view full answer...
  • Tow Bar Availability that Can Easily Store on Front of Towed Vehicle When Not In Use
    I wish we had a way to store the Curt tow bar part # C19745 vertically on a vehicle it's towing. You'd have to go with a tow bar that has more features to be able to accomplish that like the Roadmaster Stowmaster part # RM-504 which I attached a picture of that shows it stowed on the front of a vehicle.
    view full answer...
    Image 1 for
  • 2017 Subaru Crosstrek Manual Transmission Base Plate and Tow Bar Options
    As long as you have a manual transmission on your 2017 Subaru Crosstrek you can use the Roadmaster EZ2 Base Plate Kit - Removable Arms # 52922-1A which is compatible with Falcon 2 # RM-520, Stowmaster # RM-501 or # RM-504, Falcon # RM-522, Sterling # RM-576, or BlackHawk 2 # RM-422. Another base plate option is the Blue Ox Base Plate Kit - Removable Arms # BX3620. This baseplate is compatible with the Alpha # BX7380, Aladdin, Avail # BX7420, or Acclaim # BX4330. Let me know if you'd...
    view full answer...
  • Does Roadmaster Base Plate Kit Fit Tracker and Stowmaster Tow Bar
    Yes the Roadmaster base plate kit part # 1188-1 is perfectly compatible with the Roadmaster Stowmaster part # RM-504 and the Tracker # RM-020.
    view full answer...
  • Parts Needed to Flat Tow 2005 Toyota Tacoma
    There are base plates that fit your 2005 Toyota Tacoma, though the Roadmaster # RM-521196-5 base plates you referenced are not a fit. In regards to if this truck can be flat towed, I looked in the online version of the owner's manual and was not able to find any reference to if this truck could be flat towed (sometimes called Recreational Towing) so I recommend contacting your local Toyota dealer to find out if this truck can be flat towed. In regards to each of the other parts you need...
    view full answer...
  • Is the StowMaster Tow Bar Compatible with Roadmaster XL Base Plate Kit on a 2001 Mazda Miata
    Yes, the Roadmaster Crossbar-Style Base Plate Kit # 711-4 for your 2001 Mazda Miata is compatible with both the 2" Hitch Ball # RM-501 and 2-5/16" Hitch Ball # RM-504 versions of the StowMaster tow bar. I reached out to my contact at Roadmaster who did say that it will fit but he is afraid that you will be putting too much weight at the front of your Miata since the tow bar stows there. He recommended going with a motorhome mounted tow bar like the Falcon 2 # RM-520 instead since it stores...
    view full answer...
  • Parts Needed to Flat Tow 1988 Toyota Truck
    Your photo did not come through, but I looked up the tow bar you referenced and can tell you based on that it will not connect with the Roadmaster Crossbar-Style Base Plate Kit # 1146-1. We do have an option that will work for you with these base plates, the Roadmaster StowMaster Tow Bar - 2" Ball # RM-501 or StowMaster - 2-5/16" Ball # RM-504. Otherwise you would need a universal type of tow bar such as the Curt Tow Bar with Adjustable-Width Arms - Car Mount - 2" Ball # C19745 which...
    view full answer...
  • Parts Needed to Flat Tow a 2013 Jeep Wrangler Unlimited Behind an RV with Stowmaster Tow Bar
    If your 2013 Jeep Wrangler Unlimited has the standard factory bumper you can use EZ4 base plates # RM-521448-4. If it is a 10th anniversary addition but does NOT have the American Expedition Vehicles bumper you can use # 1444-1. If it is a MOAB addition OR has the Warn Elite bumper and is NOT a 10th anniversary model you can use # 1439-1. All of these base plates are compatible with the Stowmaster # RM-501 or # RM-504. In addition to the tow bar and base plates you will also need safety...
    view full answer...
  • Recommended Base Plate Kit for a 1997-2003 Ford F-150
    The base plate kits for a Ford F-150 will be the same from 1997-2003 with the exception of Lightning, Harley Davidson, and Diesel editions. As long as you do not have one of these editions then I recommend using the Roadmaster XL Base Plate Kit part # 456-15 for 4 wheel drive (4WD) models or part # 492-1 for 2 wheel drive (2WD) models. Unfortunately, we do not carry any universal base plate kits therefore this will be your best option. For a tow bar that will work with either set of...
    view full answer...
  • Can a 2018 Ford Fiesta be Flat Towed by a Ford F-150
    You definitely can use a pickup to tow your 2018 Ford Fiesta as long as the Fiesta doesn't exceed the weight ratings of the pickup or the trailer hitch. I am not sure what year Ford F-150 you are wanting to use but if you look in your owner's manual it will tell you the max weight rating for your pickup. A 2018 Fiesta should weigh somewhere between 2,500 lbs - 2,800 lbs though so your F-150 should have an easy time towing it. The Roadmaster Direct-Connect Base Plate Kit # RM-524441-5...
    view full answer...
  • Is the Roadmaster StowMaster Compatible with EZ4 Base Plates on a 2015 Volkswagen Golf TDI
    Yes, the Roadmaster StowMaster Tow Bar # RM-504 is compatible with the Roadmaster Crossbar-Style Base Plate Kit # RM-521239-4 on your 2015 Volkswagen Golf TDI. 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 do not have all of these components just let me know and I can make some additional recommendations for you.
    view full answer...
  • Base Plates And Wiring Needed to Flat Tow 2017 Lincoln MKX Behind Motorhome
    For your 2017 MKX EcoBoost, I'd recommend the Roadmaster # RM-524447-4 EZ4 base plate, which is compatible with the Stowmaster Tow Bar like # RM-504. If you don't already have them, I'd recommend the # RM-643 safety chains. To wire up the taillight circuits, I'd recommend # RM-15267. You'll also need a supplemental braking system if you don't already have one. A portable system like the Blue Ox Patriot II, # BRK2016 won't require expensive labor to install and can be moved between vehicles...
    view full answer...
  • Parts Needed to Flat Tow 2002 Jeep Liberty with Tow Ready Tow Bar
    The only way we can recommend you tow a vehicle like your 2002 Jeep Liberty with the Tow Ready Tow Bar part # 63180 is to use the adapter part # RM-025 with a Roadmaster base plate kit # 521426-1. You should keep in mind that the Tow Ready Tow Bar has a lower speed rating of 45 mph than most so you might be better off with a different tow bar like the Roadmaster Stowmaster part # RM-504 which wouldn't require the adapter either.
    view full answer...




  • Why etrailer.com?

    At etrailer.com we guarantee:
  • Highest quality tow bar for the best price.

    Our Lowest Price Pledge ensures you will never overpay for the parts you need.
  • Real product know-how.

    We make sure that the products we sell are what we say they are, and that they work the way they are supposed to work. Get real advice from a real person who has the knowledge and expertise needed to solve your problem.
  • Most detailed, accurate tow bar information available.

    Because we take providing accurate product information seriously, we take our own detailed product photos, demo videos and installation videos, as well as verify measurements, instructions, and vehicle fit information.
  • Installations, made easy.

    We love helping people and have the most highly-trained customer service, hands-on experience, step by step videos and installation instructions.
  • Fast shipping.

    Your order is automatically routed to get out of our warehouse and to your door as quickly as possible. Receive free shipping on orders over $99.
  • Personalized service for life.

    We provide one-on-one, personalized service from the ordering process through the life of your product.
  • Trusted since 1946.

    We've been serving customers since our parts store first opened in 1946 and continue to be recognized by our customers, our vendors and third parties for exceptional service.
  • Returns Policy

    Need to return an item? No problem. Please read our Returns Policy for more information.

Info for this part was:

Employee Lindsey S
Edited by:
Lindsey S
Employee Kathleen M
Installed by:
Kathleen M
Employee Shelly K
Updated by:
Shelly K
Employee Kristina F
Updated by:
Kristina F
Employee Mike S
Updated by:
Mike S
Employee Isabelle B
Updated by:
Isabelle B
Employee Amanda M
Written by:
Amanda M

At etrailer.com 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.