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  1. Anti-Sway Bars
  2. Roadmaster
  3. Anti-Sway Bar
  4. Front
  5. 1-3/4 Inch Diameter
  6. Steel w Polyurethane Bushing
Roadmaster Front Anti-Sway Bar

Roadmaster Front Anti-Sway Bar

Item # RM-1139-148
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Anti-Sway Bars

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Minimize sway and driver fatigue by improving the stability and driveability of your vehicle. The bar on this sturdy, effective anti-sway system mounts to the front axle and to the frame to balance weight transfer and reduce body roll. 1-800-940-8924 to order Roadmaster anti-sway bars part number RM-1139-148 or order online at Free expert support on all Roadmaster products. Guaranteed Lowest Price and Fastest Shipping for Roadmaster Front Anti-Sway Bar. Anti-Sway Bars reviews from real customers.
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Roadmaster Anti-Sway Bars - RM-1139-148

  • Anti-Sway Bar
  • Front
  • Roadmaster
  • 1-3/4 Inch Diameter
  • Steel w Polyurethane Bushing

Minimize sway and driver fatigue by improving the stability and driveability of your vehicle. The bar on this sturdy, effective anti-sway system mounts to the front axle and to the frame to balance weight transfer and reduce body roll.


  • Minimizes side-to-side movement to improve overall stability of your vehicle
    • Lets you execute turns and quick maneuvers with confidence
    • Allows for a level ride, even on irregular surfaces
    • Reduces driver fatigue - minimizes effort required to keep your vehicle in line
  • Diminishes effects of crosswinds, passing motorists, and shifting cargo
  • Designed to fit your vehicle and work in conjunction with its suspension system
    • Attaches to front axle and to chassis - uses weight of axle to brace frame as it shifts in turns
    • Engineered to avoid interference with most popular aftermarket add-ons and accessories
  • Made with polyurethane bushings instead of the standard rubber variety for a longer-lasting system
    • Polyurethane is durable and resistant to damage caused by oil, gasoline, and ozone
    • Less wear means less give in the system and better support
  • Constructed of thick 4140 chromoly steel for superior strength
  • Includes heavy-gauge mounting hardware, easy-to-follow instructions and bushing lubricant
  • Works with rear anti-sway bar (sold separately) for absolute stability - available on certain applications only
  • Made in the USA


  • Bar diameter: 1-3/4"
  • Limited Lifetime Warranty

Roadmaster Anti-Sway Bar Installed

Benefits of an Anti-Sway System

The Roadmaster anti-sway bar does for side-to-side movement what a good pair of shocks does for up-and-down motion. You will notice a marked improvement in your vehicle's stability as the bar works to balance weight transfer and reduce body roll. The anti-sway bar acts as a link between your vehicle's frame and its rear axle, using the axle as a brace to more effectively balance the shifting weight of your vehicle as you maneuver it. Lubricated bushings allow just enough pivot and rotation to compensate for the pressure placed on one side of your vehicle when it goes into sudden maneuvers, hits crosswinds or encounters shifting weights.

Roadmaster Anti-Sway Polyurethane Bushings

Superior Construction

The Roadmaster anti-sway bar is made of 4140 chromoly, a chromium and molybdenum steel alloy. This type of steel is considerably harder and stronger than the standard 1020 steel that is typically used in anti-sway applications. In addition, the larger diameter of the bar increases its torsional roll stiffness. The result is a bar that is not only stronger than the competition, but also nearly 30 percent better at resisting sway. The polyurethane bushings and grommets used at the attachment points are durable yet flexible, ensuring that the system is neither so rigid nor so malleable that it becomes ineffective.

1139-148 Road Master Anti-Sway Bar - Front

Replaces Roadmaster 1139-140 and 1139-206

Installation Details RM-1139-148 Installation instructions

This Product Fits The Following Vehicles

Customer Reviews

Roadmaster Front Anti-Sway Bar - RM-1139-148

Average Customer Rating:  4.8 out of 5 stars   (1063 Customer Reviews)

Minimize sway and driver fatigue by improving the stability and driveability of your vehicle. The bar on this sturdy, effective anti-sway system mounts to the front axle and to the frame to balance weight transfer and reduce body roll.


It was a scary ride prior to the install, now a 100% less sway. Just wish there was a sway bar upgrade for the rear of the Thor Outlaw.

You mentioned that you would be interested in a rear sway bar for your 2019 Thor Outlaw. I checked and we might have one available. I would need to ask you a few questions. Does your Outlaw have a V8 or V10 engine? Does it have automatic chains?
-- Etrailer Expert Jenny N - 04/25/2022


Got delivery in a timely manner. All items were as advertised and installation hardware was complete.
The Sumo Springs and heavy duty sway bars made a SIGNIFICANT difference in the ride and handling.
Would have no problem ordering from this company again. They were also very helpful and patient on the phone.


The sway bars improved the steering on the motorhome and provided a very stable ride with no sway.


Best upgrade for a class A motorhome!


Great fit with no modification necessary
Have not driven it since install. Will update on performance wise


received and installed the new Roadmaster part.

Bit extra effort solo, but completed in couple hours


These were a pretty simple install and work as advertised. I installed them by myself but could have used another set of hands due to the weight of the bar.

I recommend them.


Huge improvement in Ford F53 handling c haracteristics.


We took our first trip with these installed over the last two months (April & May 2021 4,000 miles). All three of these were put on at the same time front & rear anti sway bars with the extended length U-bolts. The RV handled great.


Very good, basically uncomplicated install. Thank you

2015 Ford F-53

This was installed along with new rear sway bar. This required a little more effort as it was not exactly a mounting match, it was ordered and was supposed to be but wasn't. The bushing brackets didn't line up to the axle mounting holes, they were offset about 1& 5/8 inch on center and caused the bushing to sit right on the curve of the sway bar. I had to make 2 adapted brackets to allow it to fit the axle mounting holes properly. It wasn't a big deal as I have machine shop and engineering back ground. It along with the rear vastly improved the sway and handling of the RV.


This Sway bar is a must add on if you own a motor home. I have a Tiffin 32sa and it handled better compared to most models that I have test driven but I wanted a better ride. I added this and a new rear sway bar system and the ride is like night and day. We also have the factory Sumo springs which is a plus as well. No more rolling into the turns. I also added a steering shock damper. No more drifting. All in all it was worth the money and saves on driving fatigue when on long trips. I highly recommend all items mentioned.

2018 Tiffin Allegro Motorhome

With the RM-1139-148 rear sway bar installed it definitely handles better than the stock chassis. However when you get up over 65 MPH it starts to give you the same characteristics of the stock chassis just not as bad. I'm glad I installed it because even over 65 It's still better than stock.


Extremely helpful and knowledgeable with selection process. Over the top with high quality customer service!!! Mary is a terrific asset!!!


Very happy with all the suspension parts I have received from them fast shipping . I will be ordering more from them in the future .

2018 Jeep JL Wrangler

Sway bar arrived quickly. Instructions were not very detailed. For my Motorhome, Winnebago Adventurer (37F), I did not need the extra bolts, nuts and washers supplied and found no reference as to where they were needed. My original sway bar was attached with 6 bolts total. Have not test driven the Motorhome to verify for myself if sway has been reduced - hence the 4 stars vs 5. BUT, the bar is bigger and hopefully will help with that. Have not installed the rear bar yet.

2019 Ford F-53

Over some years I have purchased several items from etrailer. 3 or 4 class III trailer hitches, trailer wiring harness, 4 different sway bars for class A motor homes, Reflex Steering Stabilizer and a few other items. The products have always been exactly as advertised, well packaged, good instructions and delivered in a timely manner. Communication with etrailer personnel is always easy, very detailed complete. It I need an item and it is one I plan to order on line, then odds are that I will get it from etrailer.


With all my upgrades to suspension it drives like a diesel pusher.
Very stable in wind and side loads.
I had a little trouble getting it installed as I am unable to do it myself anymore. But once I suggested they read the instructions it got done right.


This has help reduce excessive sway of my motorhome and reduce driver fatigue. I have a 2017 Allegro. A local repair shop install it for me in about an hour.

It has really made a positive improvement in the ride quality. Recently the front suspension started making groans and noises. I had to have the sway bar removed and the bushings relubed. It was lubricated when installed but the supplied lubricant failed.
John B - 12/16/2020

I made sure to reach out to the manufacture. They stated that it is best to lubricate every 3,000 miles. Roadmaster recommends this lubrication # L11404
LubriMatic Marine Trailer Wheel Bearing Grease - 16 oz. Can

-- Etrailer Expert Jordan F - 1/8/2021


The addition of these antisway bars made a world of difference. The coach didn't rock like it did before and made the drive more pleasurable for my wife. I highly recommend putting these on your gas coach.

2017 Ram 3500

I ordered on Wednesday it arrived Friday morning . Installed in less then a hour. I also got the rear sway bar from in etrailer just as fast. Good customer service.


The sway bar was the right choice For the Ford Chassis RV. It really took the sway and darting out of the Coach. It was installed on a RB37 Thor Toy Hauler Coach.


the roadmaster sway bars and the expert assistance from etrailer have transformed my motorhome which I was ready to sell to one that I can now enjoy driving.
The swaying has stopped and it feels more secure on the road.

Thanks again!


You guys are by far the best priced and best operated company I have ever done business with . From Adam to all the others that have made my purchases so easy . Thank You for your great customer service.Jeff


Polite assistance and quick with fast delivery.
so much

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