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

Roadmaster StowMaster Tow Bar - Coupler Style for 2" Ball - Car Mount - 6,000 lbs

Item # RM-501
Our Price: $570.95
You Save: $400.60
Tow Bar
Shipping Weight: 57 lbs
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With stainless steel arms, this coupler-style tow bar extends smoothly to reach your ball mount. Mounts to the base plate with quick-disconnects and stores on the front of your vehicle while you drive around town. Great Prices for the best tow bar from Roadmaster. Roadmaster StowMaster Tow Bar - Coupler Style for 2" Ball - Car Mount - 6,000 lbs part number RM-501 can be ordered online at or call 1-800-940-8924 for expert service.
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Roadmaster Tow Bar - RM-501

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

With stainless steel arms, this coupler-style tow bar extends smoothly to reach your ball mount. Mounts to the base plate with quick-disconnects and stores on the front of your vehicle while you drive around town.


  • Safely bring your vehicle along behind your RV
  • Easy hookup with arms that smoothly extend and pivot to reach the ball mount
    • Stainless steel construction of inner arms lets them slide in and out
  • Autowlok mechanism automatically locks the arms into towing position
    • Once at your destination, press the Autowlok button to unlock and disconnect
    • Release tool (RM-066 - sold separately) helps you get out of a bind
  • Quick-disconnect system lets you quickly and easily mount the tow bar on your towed car
    • Brackets on tow bar match up with brackets on base plates
  • Engineered to be super tough
    • 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 protects against rust
    • Full-length crossbar with angle iron brace provides maximum strength and support
  • Secure storage on the front of your car
    • Stays mounted on the base plate as you drive around
  • Made in the USA


  • Fits: most Roadmaster Crossbar-Style base plates
    • Will not work with Direct-Connect base plates
    • Can be used with Demco Classic base plates with adapter (DM9523062 - sold separately)
  • Application: 2" ball
  • Arm length (as measured from center of hitch ball to center of quick-disconnect bar):
    • Extended: 44-1/2"
    • Retracted: 36"
  • Weight capacity: 6,000 lbs
  • Weight: 38 lbs
  • Limited lifetime warranty

Smooth Hookup with Stainless Steel Arms

The StowMaster is designed to make hooking up your toad (towed vehicle) a smooth and easy process. The telescoping arms are able to extend to the needed length and angle to reach your RV's ball mount without the need for your vehicle to be perfectly level or in the exact right spot. The inner arms are stainless steel and will slide in and out smoothly. Supremely corrosion resistant, they'll stay rust-free and functional for the life of the tow bar.

What is Autowlok?

Once you're all hooked up, slowly pull forward and the mechanism in the arms will automatically lock into towing position when the arms are fully extended (hence the name Autowlok!). Double check that the arms are properly latched and you'll be ready to hit the road!

Auto lock

Then, when you've reached your destination and you're ready to unhook your vehicle, press the Autowlok release button on the arm of the StowMaster to disengage the internal 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 lined up behind your RV, chances are you'll experience some binding. This is the result of tension that can build up in the telescoping arm, and it can make it difficult to press the button all the way down and disconnect your vehicle. If this happens, a release tool (RM-066 - sold separately) will give you the leverage you need to force the button down.

Simple Storage: Car-Mounted Tow Bar with Quick-Disconnect


The StowMaster comes with quick-disconnect brackets to make it easy to mount your tow bar to the front of your toad. This crossbar creates a triangular frame so you can maneuver the tow bar as one piece, instead of working with each arm at a time. It also gives you the option to add on other Roadmaster accessories, such as the Guardian Rock Guard or Tow Defender.


When you're not towing, the Roadmaster StowMaster stays mounted on the front of your car. To store the tow bar, you'll slide the driver's-side arm all the way over to the passenger side and fold the arms down together parallel with the quick-disconnect crossbar. Pin the arms in place and you'll be set to drive around on your adventure; just be careful pulling into a parking spot as you'll need several inches of extra clearance.

Of course, you can also remove your tow bar and stow it away when you're not flat towing. The StowMaster folds into a pretty compact, convenient bundle, and the quick-disconnects will make it pretty easy to pop on and off.

For added protection from the elements, slip the Roadmaster tow bar cover (RM-052-3 - sold separately) over the tow bar when you're not using it.

Engineered for Excellence

FEA test

The StowMaster is engineered to be as tough and durable as possible. Throughout the design process, rigorous physical and computerized testing is done, including Finite Elemental Analysis (FEA). Each of these tests displays 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 strengthened. This process is repeated until any weak spots, particularly those found in load-bearing components, are completely removed. The result is a product that is durable, strong, and safe.

The internal self-lubricating nylon bushings also 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.

What You Need to Flat Tow

Flat towing can be a much more convenient way to take your car RVing with you than using a trailer or a tow dolly. It'll save you storage space both at home and at the campsite, and it takes less time and hassle to hook up.

To flat tow your vehicle, there are 5 basic components you're going to need: a tow bar, a base plate kit, a safety cable set, tow bar wiring, and a flat tow braking system.

For the RV Between the RV and Towed Car For the Towed Car
Hitch Tow bar Base plate
Wiring plug Safety cables Braking system
Wiring adapter cord Wiring kit/diodes

The custom-fit base plate installs on the frame of your toad so you can connect the car to your RV with a tow bar. Hook up safety cables between the vehicles to ensure that the toad does not separate from the motorhome if the tow bar becomes detached. Tow bar wiring syncs your vehicle's signal lights with your motorhome's tail lights, as required by law in most states. Finally, the flat tow braking system - also required in most states - activates the brakes in the toad when you hit the brakes in the RV, making for smoother, safer braking, and preventing wear on your motorhome.

501 Road Master Stow Master Coupler-Style Towbar for 2" Hitch Ball - Vehicle Mount - 6K Rating

Installation Details RM-501 Installation instructions

Customer Satisfaction Score:

Customer Reviews

Roadmaster StowMaster Tow Bar - Coupler Style for 2" Ball - Car Mount - 6,000 lbs - RM-501

Average Customer Rating:  4.8 out of 5 stars   (130 Customer Reviews)

With stainless steel arms, this coupler-style tow bar extends smoothly to reach your ball mount. Mounts to the base plate with quick-disconnects and stores on the front of your vehicle while you drive around town.


The adjustable arms make this tow bar simple to hook up and disconnect. I can pull up behind our RV and hook up in about 3 minuets (including the wiring for our break buddy and putting the transfer in neutral). Disconnecting and stowing the bar is even faster. Although is tow bar is locked to the baseplate and folds flat it is so easy to remove I end up taking it off and putting it in the back when we will not be towing.



The tow bar is wonderful. The only maintenance is some basic cleaning and lubricating the sliding arms. I love how easy it is to connect and disconnect.

Etrailer Expert

Mike L.


@Erik Glad to hear that! Keep up on that maintenance, and you'll get years of trouble-free service out of that tow bar...


I was slightly nervous that this would be difficult to take on and off if I wasn't on flat ground. So for I have not had any issues and I really like that it hooks up to a 2 inch ball. My jeep has a lift on it and getting things level was easy with and adjustable height mount.



The first few times I was nervous that I would mess something up on the tow vehicle or forget to hook something up. I have a printed list that I use every time I hook up or unhook my tow vehicle. We have over 2500 miles on this set up and had great luck until our return trip home this summer. One of the ring pins that holds the tow bar to the base plates came off and bent all kinds of things on the tow bar and base plate mounts. The only thing that kept the other side in place was the padlock I used as an theft deterrent. This happened about 400 miles into a 600 mile day luckily no one was hurt and things are replaceable. The first thing I did when getting replacement parts was throw away the retaining pins that come with the kit and put on padlocks on both sides. Everything is back up and running but I would not trust those pins in the future. Yes we checked the tow bar during the drive at food and gas stops. I wouldnt not recommend this set up but just be aware when something bad happens it is bad in a hurry. Roadmaster didnt really care when I called to talk about this and if they have seen this problem before. If you end up need replacement parts etrailer doesnt have much and you will need to go to Roadmaster.

Etrailer Expert

Mike L.


@Justin We're sorry to hear that happened! Keep in mind, just because a particular replacement part doesn't appear on our website, doesn't mean we can't obtain it. We add tons of replacement parts weekly so chances are we can get what you're needing!


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.


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


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


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. 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.


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.


I have been thoroughly satisfied with my Roadmaster tow bar. I use it to tow my Jeep Grand Cherokee behind my Damon RV and could not be happier with the Jeep in tow.


This tow bar is definitely worth the money, it’s high quality heavy made.
This is our second purchase from Etrailer and shipping is really fast. We ordered on Sunday night and it was delivered Tuesday.
Very impressive customer service.


Great tow bar. I've had this model before on a different vehicle. I was so happy with the prior bar I bought this one. It is as great as my first one.


I installed the kit. Didn't have many problems. It is a really stout setup. I am very pleased with the kit and very good instructions.


Had this installed on 2002 wrangler in just a few minutes. Built very well.


I really like this product. I've towed for a year with it, very strong and well built. Would purchase again.


Paula did a great job helping with my order thanks so much!!!


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



This product has held up very well. Highly recommend


Love this tow bar it is so easy to hook up & it folds up as easy.



It works great if I bought another one I would buy one just like it.


I have owned a 5k rated, this seems to be twice as heavy and much better quality.


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.



The road master tow bar is still functioning properly with no issues, a safe,reliable well made product.


every thing went smooth instructions very good 2003 wrangler


Like it alot.thank you.


Mounted up easy and looks strong. Havnt used it but I am sure it will work fine


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





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.


It’s so easy to hook up to the RV


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.



The tow bar has worked well. The videos on the installation of the base plate were very helpful. There are a couple of different covers for the tow bars, so be sure to get the right one.

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