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Bottom Support Plate for 2-1/4" OD A-Frame Jacks - 5,000 lbs
(71 reviews)
Price: $4.94
In Stock
etrailer
Bottom Support Plate for 2-1/4" OD A-Frame Jacks - 5,000 lbs
Part Number: JSP-100
In Stock
$4.94
Retail:$5.39
You Save: 8%
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- Reviews (71)
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- Videos (1)
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etrailer Accessories and Parts - JSP-100
- Camper Jacks
- Trailer Jack
- Mounting Hardware
- Plates
- etrailer
Attach a layer of support when mounting your jack to your A-frame trailer coupler. Fits 2,000-lb to 5,000-lb A-frame jacks. Raw finish with light oil allows for easy welding.
Features:
- Support plate adds stability to help keep your A-frame trailer jack from leaning
- Bottom-mounted plate attaches to the underside of your trailer frame
- Sturdy steel construction
- Weld-on installation
- Raw finish for easy welding
Specs:
- Fits jacks with 2-1/4" outer tube diameter
- Jack hole diameter: 2.29"
- Weight capacity: 5,000 lbs
- 1-Year warranty
JSP-100 Ram Bottom Support Plate for 2-1/4" A-Frame Trailer Jacks - 2,000 lbs to 5,000 lbs
Video of Bottom Support Plate for 2-1/4" OD A-Frame Jacks - 5,000 lbs
Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.
Video Transcript for Comprehensive Review: Bottom Support Plate for 2-1/4" OD A-Frame Jacks
Today, we're going to be taking a look at a bottom support plate for a 2-1/4" outer-diameter A-frame jack with a capacity of 5,000 pounds. This support plate is going to add stability to keep your A-frame trailer jack from leaning under heavy loads. It's a bottom-mounted plate that attaches to the underside of your trailer frame. It's made from a sturdy steel construction. This is a weld-on installation. It's a nice raw finish for easy welding, so there's no prep work for it. This is designed to fit jacks with a 2-1/4" outer-tube diameter.
We can tell that by taking a measurement of the diameter of the hole right here at the center of the plate. It's going to be just a hair over 2-1/4". The exact measurement is going to be 2.29", but it is designed for a 2-1/4" outer-tube-diameter jack. Again, it's going to have a weight capacity of 5,000 pounds. A few measurements I want to go over with you real quick. The thickness of the plate is 1/8".
Again, steel construction. If we take an overall length measurement here at the back, that's going to give a measurement of 8-3/4". Here at the front, that length measurement is 5-1/2". The diagonal measurement right here, it's going to be the same for the other side. That's going to measure 3-7/8".
Then from front to back right here at the center, the straight-line measurement is 3-1/2". That's going to do it for today's look at the bottom support plate for 2-1/4" outer-tube-diameter A-frame jacks.
Customer Satisfaction Score:
100% were satisfied with this product
0% of customers were not satisfied
Ratings & Reviews
4.7
71 reviews
by:
Douglas
09/14/2026
Worked perfect for my application.
by:
Rob
09/22/2026
Haven't installed it yet, but looks to be a great fit. Quick delivery and a good price.
by:
D S Blackwell
10/19/2025
My son bent the original jack plate when he did not raise the jack to pull the trailer across the yard. We hammered the bend out of the original plate, but I feared it had lost its intended strength to support the trailer. We welded on the new bottom plate and bingo, the jack support is stronger than ever. Thanks etrailer for supplying this great piece of metal and the quick shipping.
by:
RM
06/05/2026
Prompt Service and Delivery! Thank You
by:
Steven
07/09/2020
It needs to be thicker metal. My trailer came with one exactly like this one from the factory. Someone before me tried to drive off with the jack down and ripped through the old one. Which in turn bent the L out of the hitch. The hitch was so bent there was no way to repair it and mount a new jack. So I am having to replace the hitch as well as this weak plate. If this piece had been strong enough to hold instead of tearing in two, it wouldn't have bent the hitch. The jack would be ruined but then the jack was ruined anyway. It would only have cost the price of the jack. Not the jack, hitch, and this plate. Probably order a second one and add to this one. It needs to be at least twice as thick.
by:
Mark
09/02/2025
good quality thick plate fast shipping
thanks mark
thanks mark
by:
Bruce
05/06/2025
This bottom support mount is just what I need to go from 2” to 2-1/4” jack shaft for replacement to jack. Thanks eTrailer.
by:
Douglas
12/20/2025
Just what I needed
by:
David
10/27/2022
Storage crew told me to STOP when I backed into the building...when my RPod popped off the hitch ball it rolled forward about three inches, bending the existing jack mount plate and leaving the jack at an approximately 15-degree angle. Mad? -- you bet...THIS will support the lower side of the jack after the trailer repair outfit straightens the upper mount. Thanks!
by:
Sandy G
08/14/2017
While these may be good to weld on, most of the trailer jacks that I have seen are the 3 bolt triangular style. These don't work well with them since the front part is too short to cover the entire bolt hole. So these would only be useful in a weld on style jack configuration, not a bolt in.
by:
Matt P
07/03/2017
etrailer exemplifies customer service. On top of providing one of the widest selections of quality products their follow through and fast shipping keep me coming back for more.
by:
John
11/17/2019
I used two of these to convert my side mount jack to an A frame jack without replacing my hitch receiver. With a few modifications they work great! Super happy!
by:
Dan J
08/28/2019
The product I received was exactly what I ordered and appears to be of excellent quality. It was delivered in a timely manner with no issues.
I have purchased other items from etrailer.com and expect to purchase more in the future!
I have purchased other items from etrailer.com and expect to purchase more in the future!
by:
Bill
06/20/2023
A must for a frame jacks
by:
Cliff B
07/18/2020
Exactly what I needed. Even got to practice my limited welding skills to put it on. Hardest part is cleaning up the mess the old rusted out on left. I primed a painted this one after installing.
by:
Ryan
06/13/2016
The plate is as described. Unfortunately does not cover all holes on trailer completely.
by:
Grant
08/07/2023
Buying this was the easiest part of replacing the bottom plate to my trailer. I had no issues with it other than things on my trailer itself and my bad harbor freight welder. These guys really helped make this less of a headache for me.
by:
Mike
11/21/2020
I’m rebuilding a 1977 Jayco Finch pop-up trailer. With a little trimming this bottom support worked great! Just like OEM.
by:
C Mike
06/12/2025
Simple they are cut right, works great.
by:
David
02/12/2024
No longer have that trailer. But did the job..
by:
James
08/22/2019
Prompt delivery. Just what I needed. Adds much stability to my jackstand.
by:
Micah
04/06/2023
these where just what I need to fix a couple of my trailers
by:
Huston
07/28/2022
Good quality fast shipping.
by:
Robert
06/18/2023
Heavy duty lot better than stock
by:
Jrzoffroad
03/16/2024
A great and quality item to mount your trailer jack to.
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See what our Experts say about this etrailer Accessories and Parts
- Looking For Replacement A-Frame Jack MountHey Suede, thanks for reaching out. We do offer a replacement Bottom Support Plate # JSP-100 which can be welded to the frame. The top support plate is generally part of the coupler, like part # CA-5210-B for example. I hope this answers your question. Comment below if there is anything else I can do.
view full answer... - Availability Of A-Frame Trailer jack With 1.5" Outside Diameter TubeHello J, thanks for reaching out. I went thru all of the A-frame jacks we carry and I am sorry to say we do not offer one with a 1.5" outer diameter tube. They are virtually all 2-1/4" OD tubes. The only exception is the Dutton-Lainson A-Frame Boat Trailer Jack w/ Wheel # DL74MR which has a 2" OD tube. Honestly, you might have a really hard time finding a jack with a 1.5" tube. It just isn't common anymore. If you are needing a new jack, I recommend having a new support plate welded on...
view full answer... - Dimensions Of Bottom Support Plate JSP-100The Bottom Support Plate for 2-1/4" OD A-Frame Jacks - 5,000 lbs # JSP-100 you mentioned is 1/8" thick, has a hole diameter of 2.29", 8-3/4" long at the back, 5-1/2" long at the front, the diagonal sides are 3-7/8", and front to back is 3-1/2" as shown in the included diagram. I included a video of the # JSP-100 for you to take a look at.
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- Steel Thickness for A-Frame Trailer Jack Support Plates for 2-1/4 Inch JacksThe A-frame trailer jack support plates for 2-1/4 inch jacks are all approximately 1/8 inches thick. There are some manufacturer tolerances so one might be slightly thicker than the next. And models that are raw steel like # BD003135 are more uniform in size compared to the ones that are powder coated. I have included a link to the options. Not all of them are for 2-1/4 inch jacks and there is also a square one in there but the majority are for 2-1/4 inch round jacks.
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view full answer... - Highest Lift for A Frame Trailer Jack With 5,000 lb Weight CapacityWe have a jack that meets all of the requirements that you are asking about. The Round A-Frame Trailer Jack # TJA-5000S-B has a lift, or travel, of 15-5/8 inches. When this jack is fully extended, the bracket height it 24 inches. This jack also features an easily accessible grease zerk for maintenance and has a support capacity of 5,000 lbs. Since this jack doesn't come with a foot, I recommend using part # JF-1005H-Z to help stabilize your trailer. If you would like a bottom support plate...
view full answer... - Recommended A-Frame Jack Mounting Support Plate For Standard 3 Inch On Center MountThe Lippert Components # LC285318 uses a standard 3 inch on center bolt pattern. You will most likely need to drill some new holes in your coupler to allow for the standard mounting when replacing your trailer jack. I recommend the Bottom Support Plate for 2-1/4" OD A-Frame Jacks - 5,000 lbs # JSP-100 if you are concerned about the stability in that location with the additional holes.
view full answer... - Does the Ultimate Trailer Jack for A-Frame 322-RDJ-2K Have a 2" Outer Diameter? Hey Elizabeth. The Ultimate Trailer Jack item # 322-RDJ-2K has the now standard 2-1/4" outer tube diameter. We do not have an A-frame hitch with a 2" outer tube diameter and I do not know of a company that makes one. What you will need to do is replace your bottom support plate with the item # JSP-100, as this has the 2-1/4" opening to match your upper hole. Then you'll be able to use the Ultimate Trailer Jack item # 322-RDJ-2K. What model is your 1967 camper?
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Steven
7/11/2021
Like my original post, it needs to be thicker, but it works like it should. A must have for all trailers not equipped with it from the factory.