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  1. Trailer Ramp Springs
  2. M-3 and Associates
  3. Dual Ramp Spring
  4. 84 Inch Wide Doors
  5. Conventional
  6. 81 Inch Wide Spring
Conventional Ramp Door Spring for 7' Wide Enclosed Trailer - Dual Spring - 120-lb Capacity

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

Item # ERS120D81
Our Price: $300.77
Trailer Ramp Springs
This item qualifies for Free Shipping
Shipping Weight: 26 lbs
In Stock
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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 7' 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 or call 1-800-940-8924 for expert service.
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  • Reviews (267)
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  • Why etrailer?

M-3 and Associates Trailer Ramp Springs - ERS120D81

  • Dual Ramp Spring
  • 84 Inch Wide Doors
  • Conventional
  • 81 Inch Wide Spring
  • 120 lb Capacity
  • M-3 and Associates
  • Steel

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 7' wide trailer doors.


  • 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


  • Application: 7' 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.

9500470 M-3 Enclosed Trailer Ramp Conventional Springs - Dual Spring - 120 lbs - 81"

Customer Satisfaction Score:

Customer Reviews

Conventional Ramp Door Spring for 7' Wide Enclosed Trailer - Dual Spring - 120-lb Capacity - ERS120D81

Average Customer Rating:  4.7 out of 5 stars   (267 Customer Reviews)

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 7' wide trailer doors.


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.


Spring assist door ramp works perfect!


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.

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.
-- Etrailer Expert Rachael H - 05/31/2018


This unit looks real nice going to install it soon arrived in good time considering it had to ship to Alberta Canada the price is decent the tracking was perfect thanks sure are easy to deal with


Bad service

I am sorry to hear that you are unhappy with our service. I will have our customer service team reach out to you.
-- Etrailer Expert Jenny N - 09/20/2022


Already pre-assembled for the most part....I like the instruction method for setting spring tension....everything seems to be working as it should


Works great on the ramp door that I built for a storage shed to keep golf cart in.


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.

A year later and I’m still very pleased with this spring assembly. Has made my life much easier. Definitely would recommend this product.
Rick - 12/03/2020


Haven't put on yet but seems like it will be great


Great service from etrailor shipper sure beat up box but appeared OK a little tweeked but should work.


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.


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.

Im very happy I purchased the assist ramp lift. It is still working great after a year of using it.
Charlotte P - 02/02/2018


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.

Easy to install, work great. money well spent.
John W - 09/16/2020


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.


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.


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.


I reinforced the rear ramp of my aluminum trailer and needed a bigger torsion spring set to compensate for the extra weight. The information I found on made it easy to choose exactly what I wanted.
The best part was the shipping speed. I ordered it Monday and received it by Wednesday.
Not only was it cheaper than the local trailer supply it was quicker.
Easy to install and works like a charm.


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!!


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.


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.


Everything fit perfectly and worked as intended


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


Item fit perfect and has function flawlessly after I installed it !! Thank you Etrailer !!

Excellent no issues
Marty B - 07/07/2017


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.

Thanks for your review and your business, Jim. We recommend contacting a local garage door company to install this system.
-- Etrailer Expert Laura E - 01/18/2017


The gate spring worked great and still is after a year. before I was lifting this gate
by hand. This gate is several hundred pounds. With this system I can lift it with
one hand with ease,well worth the money.

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