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  1. Hitch Adapters
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  3. High-Low Adapter
  4. Fits 2-1/2 Inch Hitch
  5. Tow Bars
  6. 10000 lbs
Roadmaster High-Low Adapter for Tow Bars - 2-1/2" Hitches - 2" Rise/Drop - 10K GTW
Roadmaster

Roadmaster High-Low Adapter for Tow Bars - 2-1/2" Hitches - 2" Rise/Drop - 10K GTW

Part Number: RM57MR
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$152.10
Retail:$221.82
You Save: $69.72
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Make up for the height difference between your RV and towing system with RoadMaster's Hi-Low hitch receiver. Works as both an adapter and a drop hitch. Attaches to a 2-1/2" receiver and accepts a 2" insert. 1-800-940-8924 to order Roadmaster hitch adapters part number RM57MR or order online at etrailer.com. Free expert support on all Roadmaster products. Great prices and Fastest Shipping for Roadmaster High-Low Adapter for Tow Bars - 2-1/2" Hitches - 2" Rise/Drop - 10K GTW. Hitch Adapters reviews from real customers.
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  • Reviews (1633)
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  • Videos (2)
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Roadmaster Hitch Adapters - RM57MR

  • High-Low Adapter
  • Fits 2-1/2 Inch Hitch
  • Tow Bars
  • 10000 lbs
  • 2 Inch Rise/Drop
  • Roadmaster

Make up for the height difference between your RV and towing system with RoadMaster's Hi-Low hitch receiver. Works as both an adapter and a drop hitch. Attaches to a 2-1/2" receiver and accepts a 2" insert.


Features:

  • Allows for proper positioning of tow bar
    • Makes up for height difference between RV's hitch and towed vehicle's base plates
  • Can be used in the rise or drop position
  • Hollow steel shank
  • Powder coat resists corrosion
  • Hitch pin and clip or hitch lock sold separately
  • Made in the USA


Specs:

  • Application: 2-1/2" x 2-1/2" trailer hitch receivers
  • Drop/rise: 2"
  • Receiver size: 2" x 2"
  • Tongue weight: 400 lbs
  • Gross towing weight: 10,000 lbs
  • Length: 13-1/2" overall
    • 8-3/4" From center of hitch pin hole to center of pin hole
  • Pin hole diameter: 5/8"
  • Limited Lifetime Warranty


Notes:

  • Designed for flat towing only. Do not use to tow a trailer.
  • When using a hitch-mounted accessory, such as a bike rack or cargo carrier, the tongue weight of your hitch will be reduced by at least 50 percent.

Most tow systems require some sort of hitch accessory to either raise or lower the tow bar to an appropriate level. The "Safe Zone" for a motor-home-mounted tow bar ranges from 3" above level to 4" below. Car-mounted models must be absolutely level. Roadmaster's High-Low Drops will provide you with the necessary drop; simply flip the accessory over to achieve desired rise.



058-2 Roadmaster Hi Lo Drop Receiver - 2" Drop/Rise





Video of Roadmaster High-Low Adapter for Tow Bars - 2-1/2" Hitches - 2" Rise/Drop - 10K GTW
Video Thumbnail Video Player Dialog

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.




Video Transcript for How to Choose the Right High-Low Adapter

Hey, everyone. Ryan here at Etrailer. Today we're gonna be talking all about high-low adapters. You know, we will cover what are they, why are they used and how to figure out if your flat tow setup could use one or not. This is a high-low adapter right here, and what it does is it plugs into the hitch on your motor home and changes the connection point height from where your tow bar is actually going to get inserted and hooked up to that high-low adapter. Everyone's set up is gonna be a little bit different.

You may not need to bother with a high-low adapter at all, but from my experience, we set a lot of these flat tows up, and almost every single one of 'em benefits from a high-low adapter. In many cases that two to four-inch drop. You might be thinking, well, what's the whole point of this Why do I need to change that connection point height, right Well, the vast majority of tow bar manufacturers recommend that their tow bar be pretty much level whenever you're pulling your vehicle behind your motor home. That way it'll perform correctly. You know, you'll get the best towing experience.

Your vehicle will track better, and you won't have, you know, premature wear on your expensive tow bar. As far as I know, pretty much all of 'em out there recommend that the tow bar have connection points no greater than three inches. So you want the connection point on your towed vehicle and the connection point on your motor home's hitch to be within that safe zone. The way to figure out if you're gonna need a high-low or not is really simple. Ideally, you could take your motor home, park it on flat ground, take the vehicle that you're gonna be flat-towing, pull it up, about like this, about how you have it hooked up,, and you're gonna take two different measurements, one of 'em being from the center of the hitch pin hole on your motor home down to the ground and from the center of the attachment point on your base plate down to the ground, and if that difference is greater in three, that's when you need to start looking into these high-low adapters.

So for example, today our motor home's hitch height was 24 inches. The base plate on our Jeep, that was at 18 inches. So we had a six-inch difference, and that's well past the three-inch safe zone that we're looking for. So we opted to use a four-inch drop, lowering that connection point down to 20 inches. Now we only have a difference of two inches between our base plate and the center of our hitch pin hole, keeping us in that safe zone and allowing us to have a tow bar that's going to ride level and perform as it should.

When you take your measurements, and if both vehicles are within that three inches, then you're good. You don't need to bother with a high-low adapter. For those of you that are trying to get all the parts set up for your flat tow, and you don't actually have your base plate and everything installed yet, sometimes what you can do is check the instructions for your base plate. Some manufacturers, not all of 'em, will actually list that height and kind of give you something to work with there and go off of. So that's always an option for you to get you going in the right direction. Now, for those of you that come to find out, you do need a high-low adapter, there's quite a few of 'em out there. It's a pretty simple concept, a bunch of different sizes that you can choose from to kind of fit your needs and get you in that safe zone. Something that I've personally ran into when using a high-low adapter is the safety cables kind of falling short, and what I mean by that, whenever you use a high-low, it's going to add, you know, that extra space in between your flat tow setup. So your safety cables will have to stretch out a little bit more, and if yours are already on the tight side or a little on the short side, you know, you might run into an issue there with them breaching because you do want. You know, when everything's fully extended, you're still gonna want slack in your cables. You know, you don't want these things super tight. You know, that way when you make turns or whatever, there's some play there. In our case, ours we inchesre just a little on the tight side. I think we would've been fine without doing this, but what I did was just use some heavy duty D links here, and that bought us an extra, you know, three or four inches or whatever and just gave us a little more breathing room there, but if yours are definitely on the tight side, and you need extra length for sure, if you already have a set of cables, you know, you don't necessarily have to buy a whole brand new extra-long set. You can always look into extensions. So these ones are made by Roadmaster here. There's a bunch of different sizes of these as far as length and capacities, and that would buy you that extra space. You know, you'd put these onto the safety chain openings on your hitch, and then you'll have another connection point where you can take your safety cables' ends, clip 'em on there and extend them out. At the end of the day, you know, it's a really simple component. A lot of times it's overlooked, but it's really important to use a high-low adapter if your particular situation calls for it. You know, keeping that tow bar level, you'll get a lot more miles out of it. It's just going to, you know, provide you with a much better flat towing experience, and you're doing things the right way. So you know, if you need one, really consider picking one up and getting everything dialed in, but you know, hopefully kind of shed some light on the high-low adapter situation and helps you figure out if you can benefit from one or not.

Customer Satisfaction Score:

Ratings & Reviews

4.9

1633 reviews
Review sort icon
Make up for the height difference between your RV and towing system with RoadMaster's Hi-Low hitch receiver. Works as both an adapter and a drop hitch. Attaches to a 2-1/2" receiver and accepts a 2" insert.

by:

Rows my boat great! Does exactly what it was designed to do!



by:

Quality product. Good price. Fast shipping. Couldn’t ask for more.



by:

etrailer customized the RM-048-10 by lengthening the shaft so that it would fit through the bumper of our Class C RV and be strong enough to support the Stowaway 2 Cargo Carrier. It works beautifully! During travel there is some left to right wiggle that occurs with the carrier. We solved this problem with ratchet straps to secure both sides of the carrier. The hitch is stout and strong, and does the job! Of course we strengthened it with the clamps, so the hitch is solid and unmovable. With the custom hitch, the Stowaway 2 carrier is lifted enough so that it doesn't bottom out when traveling up or down steep hills. etrailer staff are very easy to work with, along with the brilliant engineers who communicated well with the exact details of the design to assure the build worked safely. It is an excellent hitch; worth the value. We're on the road again with all of our lawn chairs/tables, etc. in the cargo carrier out of the elements, instead of inside the RV. Great work, etrailer! Thank you! S&S



by:

Always great products and customer service is excellent



by:

As i have said before etrailer provides online instruction and video instructions. Last july I bought a complete set of parts for flat towing a jeep wrangler. I installed the complete kit myself. I relued heavily on the videos. etrailer is a great store for your vehicle accessories



by:

The tow bar rise extension was exactly what I needed to raise up the attachment point for my Roadmaster Falcon All-Terrain tow bar when pulling my Jeep Wrangler. Perfect fit and finish.



by:

Better than I had hoped! I have a front end hitch on my pickup truck for a homeowner plow to do my driveway. My new truck is about 6 inches higher than my old truck. This is a nice solid bar adapter that drops my plow back down into line perfectly! I have bought several things from etrailer. Always top quality & always cheaper than their competition!



by:

Thank You all for getting it to me sooo quickly. Love the drop down receiver, and it’s built like a tank. Etrailer has taken care of me once again, Awesome Company !!!



by:

Once again, Etrailer had just what I was looking for. This 6 inch lowering hitch allows my electric bike carrier to be lowered by 6 inches so that I do not have to lift so high to load the bikes. The extension also allows me to open the tailgate even with the bikes loaded.



by:

We purchased a new step and a lift in my tow bars. In both purchases the delivery was prompt and the items are excellent. My wife says call etrailer when I need a part. Thank you.



by:

the roadmaster 10 inch drop adapter is heavy duty and just what I needed, Dietrich did a great job.



by:

This part made the Motorhome and tow vehicle within 1/2 inch being level which made it easier to connect and disconnect.



by:

E trailer has been bery helpful. Great service and knowledgeable customer service!

Hitch is very solid and works well.



by:

Very strong hitch adapter. If you need to extend your hitch up or down I recommend this one.



by:

This drop down hitch by Roadmaster is extremely well made. Welds are strong and steel is heavy gauge. Has a nice shiny black finish. Very satisfied.



by:

Fits well, seems well constructed. Its heavier than i expected, very solid. Haven't used it yet, but it is on the camper and ready to go. We have a LOD bumper on the Bronco, that is designed for towing and the adapter gets the tow bar even with the Bronco's tow points. The round D-Ring holes are 27 inches off the ground.



by:

Great adapter to level the tow kit out that I bought from E-Trailer! Shipped the same week and arrived at the house along with the rest of the order. Has held up to multiple tows of the Ford F150 behind the bus.



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Fits very well. Just what I needed.



by:

It will not slide in my 2 1/2 reciever. It appears to have too thick of powder coat that I will have to grind down. For reference my reciever is a Curt 20000 pound for ford f550 chassis cab



by:

Works perfect.



by:

Nice, sturdy, but I wasn’t careful and ordered the wrong thing. This fits 2-1/2” receivers, I never knew there was such a thing. I was able to buy a 3” to 2-1/2” sleeve locally to make this drop hitch work.


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See what our Experts say about this Roadmaster Hitch Adapters

  • How Can I Go From a 2 1/2" receiver to a 2" with a 2" Drop for Motorcycle Carrier?
    Hello Kenneth, Welcome to etrailer! I'm glad you found us. Thanks for getting that additional information to me. Since you only need a 2" drop to get your carrier to clear your tailgate, these are your best options: If you only need to go down 2", we have the Roadmaster High-Low Adapter for Tow Bars - 2-1/2" Hitches - 2" Rise/Drop - 10K GTW # RM57MR, it goes into a 2 1/2" receiver, then the bottom receiver will be 2". It has a 400 pound tongue weight rating so it is strong enough for...
    view full answer...

Info for this part was:

Employee Lindsey S
Edited by:
Lindsey S
Employee Chris R
Video Edited:
Chris R
Employee Wilson B
Updated by:
Wilson B
Employee Michael B
Installed by:
Michael B
Employee Andy C
Installed by:
Andy C
Employee Amanda K
Written by:
Amanda K

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