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  1. Trailer Ramp Springs
  2. M-3 and Associates
  3. 6 Foot Wide Trailer
  4. 7 Foot Wide Trailer
  5. Dual Ramp Spring
  6. 86 - 120 lbs
Conventional Ramp Door Spring for 7' Wide Enclosed Trailer - Dual Spring - 120-lb Capacity
M-3 and Associates

Conventional Ramp Door Spring for 7' Wide Enclosed Trailer - Dual Spring - 120-lb Capacity

Part Number: ERS120D81
In Stock
$377.79
Trailer Ramp Springs
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Replace your old trailer door spring with this heavy-duty system. This dual-spring setup lets you easily open and close the ramp door on your enclosed trailer and eliminates the risk of it freefalling. Fits 60 to 82 wide trailer doors. Great Prices for the best trailer ramp springs from M-3 and Associates. Conventional Ramp Door Spring for 7' Wide Enclosed Trailer - Dual Spring - 120-lb Capacity part number ERS120D81 can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
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M-3 and Associates Trailer Ramp Springs - ERS120D81

  • 6 Foot Wide Trailer
  • 7 Foot Wide Trailer
  • Dual Ramp Spring
  • 86 - 120 lbs
  • Torsion Spring
  • Conventional Spring
  • 81 Inch Wide Spring
  • 150 Inch Cable
  • M-3 and Associates

Replace your old trailer door spring with this heavy-duty system. This dual-spring setup lets you easily open and close the ramp door on your enclosed trailer and eliminates the risk of it freefalling. Fits 60 to 82 wide trailer doors.


Features:

  • Ramp door spring lets you easily lift and lower the door on your enclosed trailer without risk of injury
    • Helps to take on the weight of your trailer door so you don't have to
  • Dual springs eliminate the risk of the ramp door collapsing and causing damage or injury
    • If one cable falters, the other spring will prevent the trailer door from freefalling
  • Spring reduces wear and helps prevent damage to door hinges
  • System can be modified to fit your specific application
    • Slide the bracket and cable drum down and cut the shaft to a shorter length
  • Yellow safety covers install on top of the bolt heads to prevent any unwanted adjustments
  • Sturdy steel construction
  • Made in the USA


Specs:

  • Application: 60" to 82" wide trailer door
  • Dimensions: 81" wide
  • Spring capacity: 120 lbs
  • Cable length: 150"
  • 1-Year limited warranty


Warning: It is recommended that only individuals who have experience winding torsion springs install this product. If you have not worked with a torsion spring system before, we recommend contacting a local garage door company to install this system.



9500090-ET M-3 Enclosed Trailer Ramp Conventional Springs - Dual Spring - 120 lbs - 81"

Replaces M-3 9500470





Customer Satisfaction Score:

Ratings & Reviews

4.6

438 reviews
5 Stars
(351)
4 Stars
(49)
3 Stars
(12)
2 Stars
(4)
1 Star
(22)
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by:
Works great on the ramp door that I built for a storage shed to keep golf cart in.
by:
Just what it said it was.
by:
Website is easy to navigate with a large selection of parts. Part was in Stock with same day shipping. Part was delivered on time and was an exact fit. I was notified from the time it shipped to the time it was delivered. Outstanding Customer Service. 5 Stars.
by:
I installed this on a heavy fold-down ramp door that I made for hauling my Jeep in an enclosed trailer. The ramp was so heavy that I couldn’t hardly lift it by myself. I bought the dual spring model because I thought I needed it, but I don’t. One spring is all I needed. I can now lift the heavy ramp door with one hand.
Rick profile picture

Rick

12/3/2020

A year later and I’m still very pleased with this spring assembly. Has made my life much easier. Definitely would recommend this product.

by:
Directions can be a little confusing, since I installed this on a she door, not a enclosed trailer. Left and right are painted and all was clear except on which way cable winds on drums, according to rep you wind it thru front unlike a garage door. Called to confirm because drums are labeled r and l but are reversed as your installing it,which prompted a call call.
Rachael H. profile picture
Etrailer Expert

Rachael H.

5/31/2018

Thanks for the follow up Brandon. This system is set up so that when you are in the trailer or shed in your case looking out of the down door, the end with the black cable drum and the red winding cone should be on your left. If you are not comfortable or experienced with the installation of torsion springs, it is highly recommended that a local garage door company complete the installation.

by:
Package was delivered totally destroyed and I’m guessing that parts are missing because there is no mounting hardware.
Victoria H. profile picture
Etrailer Expert

Victoria H.

2/20/2025

Oh this shouldn't have happened to you Allen! Let me help make this right for you.

by:
I ordered the assist ramp lift because my ramp door was too heavy for me to lift by myself. After installing the assist lift correctly a 12 year old can lift the ramp door using only one hand. I recommend this product and the price is very reasonable for what you get with this company.
Charlotte P. profile picture

Charlotte P.

2/2/2018

Im very happy I purchased the assist ramp lift. It is still working great after a year of using it.

by:
Very easy to order, Quick deliver, the parts arrived in good condition even thogh the boxes was ripped open during shipping, I have not had time to install it yet o
. so no picture is available.
John A. profile picture

John A.

9/16/2020

Easy to install, work great. money well spent.

by:
This enclosed trailer door ramp spring pulley system is great. It is so smooth unlike the one that came wiyh my pace American trailer. Doesn't grind or squeek. Does exactly what it is supposed to for an outstanding price! Trust me, I did the research. I had to install by myself and it wasn't bad at all. Should have read the directions first so I had it turned around the wrong way. Lol. But it was a 2 minute fix to get back on track. I really am glad I found this.
Definitely would recommend.
by:
Everything fit perfectly and worked as intended
by:
Yes, I know it is recommended for personnel whom have utilized a torsion spring before, but I am definitely on the stubborn side. Before I could contact my local garage door guy, I pulled this out of the box to see if I needed to make a modification. So, I shortened the bar. I then noticed that the old one had to come down. Then I happened to notice that the placement of the plate almost lined up to the old one. Two minutes later, I was too far in the installation to not finish this job myself. Total time it took me was 1hr45min. 15 of those minutes were spent unwinding the cables because I didn't read the directions to put it on with the ramp down. Other than that, it was a breeze. Customer service was also the most amazing experience ever. I called to make sure I was ordering the right part from Pace and they informed me that my trailer was to old and to go to a recommended dealer 30 minutes away. etrailers crack staff told me to go out and measure my trailer twice, to make sure it would fit. Voila, 2 minutes later, i knew I had the right part.
by:
This is a very good door opener at the best price I could find and very fast shipping thanks Buddy D
Buddy D. profile picture

Buddy D.

11/6/2017

Still working great

by:
Best service ever, I was packing for an a tv trip and the spring broke as I closed the rampthree nights before leaving. Trailer saved my vacation big time by shipping quick and the video really helped a lot. Thanks etrailer
by:
As expectef
by:
The mounting plates are adjustable so there adjusted to fit my Pace 16' trailer perfectly. I had to install the cable pulleys backwards from what the directions called for and with the set screws facing the outside walls as well.

I installed mine with the door closed not open against what the directions say as well. When you put some tension of the springs with the door closed you must stretch out the springs some before using the set screws. If the springs are not stretched out some the door will barely open and stop because the springs will have to room to turn and expand.

The real trick is getting the cables wound up even and tightly. I needed my parts ASAP so I paid next day air which was very cheap for such a large part.
by:
First off, Deborah was awesome to deal with and had the ramp door spring shipped super fast. Thank you!
I had never installed a torsion spring and this one took me two hours, including removal of the old one off a Pace cargo trailer. You might need to cut off part of the tube ends to fit your application. I put a grinding wheel on my skilsaw and chopped off 3 inches from each end. I used my existing mounts on the header and so I removed the ones on the new spring assembly...4 bolts. The mounting plates on the assembly are easy to slide to fit my application. Installation onto the header was very quick and easy. Again, four bolts that are a bit soft and easy to strip...I used my existing hardened bolts that were exact match in every respect...only harder alloy. The cables came next. I suggest using existing hardware if it's in good shape. The provided pins and cotter pin mount left too much slop at the ramp. Good bolts and a good locking nut was what I used and allowed for plenty of relaxed movement without compressing the eye of the cable end. Vise grips come in handy when rolling the cable on the drums as you'll want to keep the bar assembly from moving while loosening the drums to roll up the slack of the cables...tighten the two set bolts on each drum and you're ready to start winding the springs. Make sure the BLACK drum is mounted to your left while looking out from inside the trailer or the entire assembly will need to be flipped. I used some rebar for winding rods and ground them down a touch to fit easily inside the cavities of the spring winder. This worked well for me, but the proper winding rods are no doubt safer and should be used or simply get a professional garage door company to do the winding part and balancing for safety reasons. Once wound according to the instructions, lock the set bolts onto the rod and you can remove the winding rods. I used the top of my trailer to help hold the rod while tightening the set bolts...all the while holding another rod in the cavity for safety. From there, you will want to readjust your drums on the cables to get an equal amount of tension on each cable. One cable will likely be a lot tighter while the other relaxed upon rasing the ramp. With the door up and closed, loosen the drum set bolts on the LOOSE cable drum and spin it to get a tighter cable and lock the bolts back into place. Raise and lower the door a time or two and go back into the trailer with the door closed and readjust the drum that has cable slack until they are fairly equal.
That was it and other than the appeals for safety around the entire process, it was easy to do.
Unless you are used to working around stuff like this, I think having a garage door company wind the springs and adjust the drums would be money well spent to avoid any potential injuries. I doubt it would cost much because that part goes pretty quickly and they would have the experience to do it in about 15 minutes or so.
by:
Exactly what it says it is. Looks like a nice piece. Easy installation. Best deal on the internet. I searched for probably hours trying to find a better deal and you wont. They didnt have it in stock but ended up shipping it straight to me and I had it before they thought I would. Great Service. Very easy to work with. Will always come here and look for future trailer parts.
by:
Product came in a timely matter through UPS. Installed it with no problem at all but you MUST read the instructions first so that you know what you're doing. Turned 38 quarter turns and then a few more (4) after that. Not sure if I should do a few more turns because the ramp door still takes two hands to close.
Laura E. profile picture
Etrailer Expert

Laura E.

1/18/2017

Thanks for your review and your business, Jim. We recommend contacting a local garage door company to install this system.

by:
good product
by:
Trailer door extra welded extra heavy. This spring has worked great for a year so far, never pushed its limits but never didn’t trust it.
by:
Very satisfied, will for sure come back
by:
Item fit perfect and has function flawlessly after I installed it !! Thank you Etrailer !!
Marty B. profile picture

Marty B.

7/7/2017

Excellent no issues

by:
I've order many items from this company. First website is perfect very quick,also every item u may need with a item your ordering is shown (such trailer wiring connectors and so on) shipping is fast as we can ever ask. And all information for products is available including wiring diagrams and ext. Hands down great company.Just keep it up!!
by:
Bought this spring assembly for my 7x14 enclosed trailer ramp door. Delivery was quick and it fit perfect. Its been a full year and still working well. If i remember correctly a friend and I installed it in about an hour.
by:
Fast shipping. Great product and easy install.
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Show More Reviews

See what our Experts say about this M-3 and Associates Trailer Ramp Springs

  • Choosing/Sizing the Correct Trailer Ramp Spring for a Ramp Door
    When selecting ramp springs for a trailer ramp, you will want to know the diameter of your hinge pin and how much space you have available in the hinge. A typical horse trailer or utility trailer ramp uses 3/4 inch hinge pins and would require two ramp springs with a 3/4 inch inner diameter. The ramp springs that we carry fit 1-1/2 inch diameter hinge pins and are designed for use with heavy-duty steel ramps like those on equipment trailers or car haulers. The spring slips over the hinge...
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  • What Size Ramp Door Spring Do I Need for My Trailer?
    Hello Vance, Awesome job on building your trailer! I am happy to find the right spring for you, but in order to do I am going to need quite a few measurements. I have included a picture of what measurements I need, can you please respond back with the measurement for each letter?
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  • Looking For Ramp Spring For 2989 Bumper Pull 2 Horse Trailer Ramp
    Hello Maureen, thanks for reaching out. We may have a ramp spring assembly that will work for you, but there is no way to look up your trailer to know which one will work. I would need to know the width of the ramp, as well as the approximate weight of the ramp. You may be to do a single spring depending on what size door you are working with. The cable would not be detachable though. They would be very much permanent. Let me know those specs for your ramp and I am happy to look into...
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  • Weight of Enclosed Trailer Ramp Spring ERS120D81
    Though I can't give you a reason why, I can tell you that the Enclosed Trailer Ramp Spring # ERS120D81 has a shipping weight of 27 lbs, which is going to be very close to what the actual product weight is. It is 81 inches wide with a 120 lb capacity and has 2 springs on the assembly. I've added a link to a video review of this product for you to take a look at as well.
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  • How is M3 Enclosed Trailer Ramp Spring ERS120D81 Measured
    The M3 Enclosed Trailer Ramp Spring # ERS120D81 is 81-inches wide as measured tip to tip; this is noted in the linked video at the :45-second mark. The installation instructions for this product are recommended for individuals who have experience winding torsion springs. If you have not worked with a torsion spring system before, we recommend contacting a local garage door company to install this system.
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  • Is There A Lift-Assist Available For An Enclosed Trailer Ramp Door
    Hey Dennis, To my knowledge there isn't a lift-assist for an enclosed trailer door so the only option we can offer would be to swap out the door spring from a single # M374FR to a dual spring system like # ERS120D81 to give you a bit more balance and strength holding the door. There are other weight capacities available as well to choose from so the # ERS120D81 might not be the correct fit depending on how heavy your door is because if we go too heavy your door will try to lift up on its own.
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  • Where to Install the Control Box on the GE Appliances Deluxe Plus RV AC System
    Hey Ben, welcome back. We haven't had a chance to install the GE Appliances Deluxe Plus RV AC System w/ Heat item # GE94RR, so I don't have a video to reference. I took a look at the instructions, that I have linked below, once you get the AC Unit installed on the roof. The control box is going to attach to the mounting template just like the picture you sent.
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  • How to Pick Out Replacement Cable Length for Trailer Torsion Ramp Spring
    You would want to measure from the bottom of the ramp door all the way up to the spring above the door frame when it is open to determine the minimum length cable you would need for your spring. We do offer cables alone for enclosed trailer ramp torsion springs. Part # CAB1-8CB150 is a pair of 150-inch cables. The installation instructions for this product are recommended for individuals who have experience winding torsion springs. If you have not worked with a torsion spring system...
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  • Recommended Gate/Ramp Assist and Hinge for Trailer Build
    The 2K Torque Ramp Spring # RS16933RH is an industrial strength spring. It is designed for up to 90 degrees of deflection, but most people by hand can cause no deflection at all. It is designed to be used with the LH # RS16933LH, and is for heavy ramps or doors like in the attached photo. I would assume it is too strong for your application based on your wording. You may want to consider a different style spring like the Enclosed Trailer Ramp Spring - Dual Spring, 81" Wide # ERS120D81...
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  • Solution for Trailer Torsion Ramp Spring that has Either Too Much or Too Little Lift Assist
    Yes, it sounds like your springs are too heavy duty which is making them nearly impossible to find the "sweet spot". Your current spring has a 160 lb capacity which for a lighter style of ramp spring we have the part # ERS120D81 that has a capacity of 120 lbs and would give you the ability to find the sweet spot in terms of ramp tension.
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  • Recommended Spring to Help Close Ramp on a 2006 Gearbox Toy Hauler
    The Enclosed Trailer Ramp Spring # ERS120D81 that you referenced is an excellent option to help you lift the ramp on your 2006 Gearbox Toy Hauler. It has a 120-lb weight capacity so if your door weighs over 120 lbs, say 150 lbs for example, then you would only be having to lift that extra amount, which for example would be 30 lbs. The 81 inch width will fit great once installed since your door is 96 inches wide. If you do not have experience winding torsion springs then we recommend contacting...
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  • Parts Needed To Convert Double Door On Enclosed Trailer To Ramp Door
    There are options for you, and it really comes down to how much of the fabrication you are able to do yourself or if you are going to have to have someone do the work for you. The most cost effective way is reinforcing your double door and converting it to a ramp. You will need to change the hinge to one like the 3" Wide Continuous Stainless Steel Hinge # SH300 and then add a new latch like the # 305736 on each side to keep the door closed. You will then need to have a ramp door spring...
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  • Using an Electric Winch to Raise and Lower a Ramp Door on a Logan Horse Trailer
    With an Enclosed Trailer Ramp Spring # ERS120D81 when the door is lowered it will pull the cables which will turn the pulleys and put tension on the springs. The cables could not be detached with the ramp door lowered because the springs would suddenly lose tension and they could break and that is very dangerous. What I recommend doing is just using a winch with a system of pulleys (or you could mount the winch above the door at the center so you won't have to use pulleys). Once the door...
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  • Choosing the Correct Ramp Springs for Enclosed Cargo Trailer
    The springs you mentioned are designed for use on ramps that you'd typically see on a heavy equipment trailer. They're way too stiff to be used on a trailer door. The correct springs for your application will depend on what you are using the ramp for and the width of the trailer. The Ramp Springs you are asking about are best used for heavyweight steel doors on a horse trailer or for an enclosed car trailer. If one man can lift the ramp, a more lightweight option like a torsion spring...
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  • Ramp/Door Spring Recommendation for 2011 Homesteader Enclosed Trailer
    Sounds like you are looking for a rear door/ramp spring kit for your trailer. For that we have the Enclosed Trailer Ramp Spring # ERS120D81 which would work well. This should work well for you but I also attached a picture of it's dimensions for you to compare to your trailer.
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  • Recommended Ramp Door Spring for 6x12 Enclosed Trailer
    When selecting ramp springs for a trailer ramp, you will want to know the diameter of your hinge pin and how much space you have available in the hinge. A typical enclosed trailer ramp uses 3/4 inch hinge pins and would require two ramp springs with a 3/4 inch inner diameter. The ramp springs that we carry fit 1-1/2 inch diameter hinge pins and are designed for use with heavy-duty steel ramps like those on equipment trailers or car haulers. The spring slips over the hinge pin and requires...
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  • Replacement 120 Cables for Trailer Ramp Door
    I believe you're looking for the 150" Replacement Cables for Conventional Ramp Door Spring # CAB1-8CB150 that comes with the Kit # ERS120D81 rated for 120 lbs. If you're looking for something else please let me know and I'll be more than happy to help you look into it!
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  • Ramp Door Spring for 72" Wide Door on Wells Cargo Trailer
    What you can do is use Enclosed Trailer Ramp Spring - Dual Spring, 81" Wide # ERS120D81 which will work for doors which go down to 62 inches wide. You can take a look at the video review of this product I've added for you.
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  • Cable Length Recommendation for Having 115 Inches from Ramp to Spring for Trailer Ramp Spring
    Since you need 115 inches of cable between the spring and the ramp the size cable I would recommend is the 150 inch cable part # CAB1-8CB150 and you'd be set.
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  • How Many Turns of Spring is Recommended for M-3 Enclosed Trailer Ramp Spring # ERS120D81
    I checked with M-3 and when you are ready to wind the spring on the Enclosed Trailer Ramp Spring # ERS120D81 you will need to use two 1/2 inch diameter bars (of around 18 inches long). You will insert the first bar into the winding cone of the spring and pull down. The system is then designed for 10 full revolutions of the spring. It will be easier to balance the door if the spring is wound in quarter turns. Please note that we highly recommend only installing this if you have had previous...
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  • Replacement Springs for Ramp Door on Continental Cargo Enclosed Trailer
    I believe you're referring to the # RS16933LH spring, is that correct? These springs aren't meant for an enclosed trailer with a ramp door, they're meant for the very heavy steel ramps you'd typically see on the back of a trailer used to haul heavy equipment like bulldozers. Your best bet would be to use a ramp spring like what you're already using, like part # ERS120D81. Installation of springs like these can be extremely dangerous, due to the tension stored in the spring. If you aren't...
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  • Replacement Left Hand Drum for M-3 Dual Ramp Springs
    We actually carry the replacement left hand drum # DRUM-M-3LH which is for M-3 Dual Ramp Springs # ERS120D81 and # ERS160D96. Since this can be a tricky installation we do recommend that only someone with experience (like a local garage door company) do the install. If you have a different spring that we don't carry then you'll want to reach out to that manufacturer for replacement parts as these aren't necessarily universal pieces.
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    Image 1 for
  • Ramp Spring Recommendation for Rear Ramp of Toy Hauler
    You could install a ramp spring like the part # ERS160D96 at the top of your ramp opening to assist the ramp in lifting and lowering. That part number is for a 96 inch wide assembly but if you needed a smaller one we have the part # ERS120D81 which is 81 inches wide. These are torsion spring style assists that would need to be wound by a professional.
    view full answer...


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