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Dump Door Hinge for Dump Trailers - Steel - Qty 1
Polar Hardware

Dump Door Hinge for Dump Trailers - Steel - Qty 1

Part Number: PLR1904-Z
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$17.49
Retail:$18.39
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Upgrade or replace a damaged hinge on your dump trailer's access door or barn door-style gates with this heavy-duty hinge. Raw finish makes it easy to weld. Grease zerk fitting lets you easily grease pin for smooth and long-lasting operation. Great Prices for the best trailer door hinges from Polar Hardware. Dump Door Hinge for Dump Trailers - Steel - Qty 1 part number PLR1904-Z can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
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  • Reviews (185)
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  • Videos (1)
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Polar Hardware Trailer Door Hinges - PLR1904-Z

Highlights

  • Heavy-duty steel construction: Made of durable 1/4" thick steel for long-lasting use.
  • Versatile hinge design: Suitable for both left and right-hand side installations.
  • Wide opening capacity: Capable of opening over 180 degrees for easy access.
  • Easy maintenance: Grease zerk fitting for smooth, hassle-free operation.
  • Weld-on installation: Raw finish simplifies welding to trailers and doors.
  • Ample pin dimensions: 4-3/4" long with a 1/2" diameter for robust hinge support.

Features to know about

Ultimate Strength and Durability: Heavy-Duty 1/4 Inch Steel Construction

When you're hauling heavy loads, having strong and reliable hinges is crucial. The Polar Hardware Dump Door Hinge is crafted from robust, 1/4 inch thick steel. This high-grade material ensures the hinge is remarkably durable, standing up to tough conditions without bending or breaking. It’s built to last, making it perfect for demanding applications like dump trailers and heavy gates, ensuring your projects carry on without interruptions.

Simple and Effective Maintenance: Built-In Grease Zerk Fitting

Keeping equipment in top condition can be a hassle, but the built-in grease zerk fitting on this hinge makes maintenance incredibly simple. This practical feature allows you to effortlessly grease the hinge pin, ensuring smooth and long-lasting operation. You'll be able to keep your hinges in great shape with ease, reducing friction and wear for a consistently smooth swing.

Versatile and Easy Installation: Weld-On Design for Custom Fit

Installing hinges can sometimes be a complicated task, but not with the Polar Hardware Dump Door Hinge. Its design features a raw, unfinished surface for easy welding, allowing you to customize the fit to any trailer or gate. The weld-on design ensures a secure, robust attachment, giving you confidence that your gates and doors will swing perfectly every time.

Dependable Performance: Precision Greasable Pin

A good hinge needs a reliable pin, and the Polar Hardware hinge is equipped with a precision 1/2 inch diameter greasable pin for dependable operation. This ensures minimal play and maximum stability, even under heavy-duty use. For applications like dump doors, where precision and reliability are key, this pin delivers consistently smooth performance.

Flexible Application: Opens Beyond 180 Degrees

When it comes to maneuvering and accessibility, the Polar Hardware hinge shines with its ability to open beyond 180 degrees. This flexibility lets you fully open doors and gates to their maximum range, optimizing accessibility for loading and unloading. Whether you’re working with trailers, gates, or other large panels, this hinge offers the versatile movement needed for efficient operation.

Specs

Dimensions

  • Overall hinge length: 5-1/4"
  • Mounting bracket dimensions: 3-5/8" tall x 1" wide
  • Material thickness: 1/4"
  • Interior space: 3-1/8"
  • Pin dimensions: 4-3/4" long x 1/2" diameter
  • Usable length: 2-7/8"

1904-Z Polar Hardware Dump Door Hinge - Steel





Video of Dump Door Hinge for Dump Trailers - Steel - Qty 1

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




Video Transcript for Comprehensive Review: Dump Door Hinge for Dump Trailers

Today we're going to be taking a look at a dump door hinge from Polar Hardware. This door hinge is designed for ranch or heavy access doors. It's also known as a barn door hinge. The bracket and leaf are constructed of 1/4 inch thick steel. Very strong, durable, design. It does have a plain, also known as a raw finish, which is going to allow for easier welding when it comes to the installation.

The bracket is the portion that gets welded to the trailer. The leaf, or plate, gets mounted to the door. It does come with a grease fitting. That's a Grease Zerk fitting for longer life as well as smoother operation. What you can do is, you can frequently pump grease in by attaching a grease gun. Pump the grease in.

That's going to lubricate the pin, or that bolt that runs through. It's going to allow for easy operation, and overall it's going to extend the life of the hinge. In this position, so this would be what's considered the mounted position with the door in the closed position. If we measure from the back of the bracket to the end of the plate, in this position, that's going to give us a measurement of about 4 inches. If it's a little bit more squared off like as if it was actually installed, we're looking at a length measurement of right around 4 inches going that direction. That's measuring from the back of the bracket to the end of the plate.

If we stretch it all the way out to where it's as flat as can be, and go edge to edge, that's going to give us a measurement of something a little bit closer to 5 inches long. The plate portion. This is going to have a width measurement of 2 7/8 of an inch. Again, 1/4 inch thick steel. If we measure that flat side right there, that's going to give us a measurement pretty close to an inch and a half, right in that area, as you can see. Maybe 1 9/16 of an inch.

The bolt, that's going to give us a length measurement from end to end of 4 3/4 of an inch. The bracket, that's going to measure 3 5/8 by 1 inch. That's going to do it for today's look at the dump door hinge from Polar Hardware.

Customer Satisfaction Score:

Ratings & Reviews

4.8

185 reviews
Upgrade or replace a damaged hinge on your dump trailer's access door or barn door-style gates with this heavy-duty hinge. Raw finish makes it easy to weld. Grease zerk fitting lets you easily grease pin for smooth and long-lasting operation.

by:

Excellent product, a little more expensive than the cheap alternatives on (another site) but worth it in my opinion. Made in USA by polar and looks very heavy duty.

Gwendolyn Y. profile picture
Etrailer Expert

Gwendolyn Y.

2/28/2025

Hey Cody. Install looks great!



by:

Easy to install and durable

Victoria H. profile picture
Etrailer Expert

Victoria H.

3/26/2025

It looks pretty good installed too, Shawn! Is this something you're making or a repair?



by:

I can't rate these yet on usage,but based on the construction thereof. I can tell you they are well built and will be using them on 2-- 50 inch wide by 8ft high wooden doors on my cistern tank house that has 2 -2500-gallon tanks. I welded them to 5x6 plate steel but have yet to finish my project due to a lower back problem.



by:

Used for a 30' flag pole hinge, holds up great



by:

Worked perfect for my load trail dump trailer door



by:

Very well build hinges. Much better than the Chinese Amazon ones. The back of the formed barrel was welded and it has bronze bushings instead of plastic.



by:

I used these hinges to attach a spare tire rack to the back of our Toy Hauler. The effort of crawling under a trailer and wrestling a 70 pound spare tire out didn't make sense. So I attached a set of these to a tire carrier for a Chevy Astro Van. Bolted it all together and still have easy access to the back garage door/ramp.

Larry A. profile picture

Larry A.

7/15/2019

Absolutely great!



by:

Looks very solid , I haven't used them yet on my project but buy the feel and look of them I don't expect to have any problems with them

Brooke M. profile picture
Etrailer Expert

Brooke M.

3/7/2025

Wed love to see a picture of the finished project if you feel like sending one in :)



by:

Used this for an off-road trailer, spaced the door and 8th inch and used 1/4 inch weatherstripping, seals perfectly



by:

Quality items worked as intedended as swing gate henges for dump trailer.



by:

Very quick delivery! Good quality, very heavy duty.



by:

Trying now to find door hook that holds the door open when dumping



by:

Making good use of them as hinges for adjusting the inclination on my solar panels. Spreading about 600 lbs out over three hinges.



by:

Wow! This little hinge is amazing! Please buy 50 of them right now! Stock up! The apocalypse is coming and you will need these. The picture is my backhoe and has absolutely nothing to do with this part.

Mike L. profile picture
Etrailer Expert

Mike L.

7/1/2019

Nice backhoe! It looks like youre well-equipped for any future apocalypse!



by:

Cam latch and dump gate 270 hinges worked out great. Delivery was on time!



by:

No complaints really. You have to flip the bolt if it is a left side hinging door or gate, but I guess that is more cosmetic than anything since there isn’t a chance that the nut would back itself off. I like bolt head up. Time will tell how good the product is or isn’t.



by:

On Time perfect product



by:

My grandson welded it and it’s working perfectly.



by:

When installing drop down gates on a trailer or deck, these are handy little hinges.
They weld easily, move smoothly, and with the lube zerk fitting, should last pretty well. My installation is on the rear of a tilt down trailer deck, with a "2x4" steel rear gate that drops down to drive over for loading. These hinges look strong enough to hold up to the job.

Carl profile picture

Carl

9/1/2019

All is good one year later! Tilt deck trailer and flip down back gate that gets driven on by cars and tractor. Hinges have held up well as have my welds!. Very versatile and useful hinges.



by:

GREAT PRODUCT



by:

Placed hinges on a custom dump trailer. They have been wonderful!



by:

These hinges are great. I welded 2 of them onto each side of my custom barn doors on my dump trailer. The doors also fold down for a ramp. I ran my 11,000lb skid steer up the ramps and these hinges did end up bending or flattening out a little. So I cut them off and reinforced them a little with a side gusset plate so they couldn't stretch. I have since added 2 more on each side for added strength. Needless to say, they are built very well, grease zerk too. I would recommend them.



by:

Product shipped in a timely manner and was exactly what we were looking for to make the necessary repairs.



by:

Exactly as described. Worked great. Will order for more projects again soon.



by:

I own a custom shop where we work on furniture and fixtures mostly for restaurants and bars - so I may not be the typical customer looking for trailer parts, but I do have a fair amount of experience in fabrication. These hinges are going into a large sign out front of a high end restaurant holding a steel door and will see a good amount of use.

The pics on the site looked ok, but when the hinges showed up at my shop, I don't know how eTrailer puts out this level of quality at this low of a price.

Hope they don't catch on to how great of deal these are ! Lol.

I'd recommend these to anyone looking for rock solid greaseable hinges.


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185
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See what our Experts say about this Polar Hardware Trailer Door Hinges

  • Does Dump Door Hinge PLR1904-Z Have Weight Capacity
    The Polar Hardware Dump Door Hinge, Steel # PLR1904-Z that you referenced does not have a weight rating. I spoke with my contact at Polar, and he confirmed that they do not have a weight rating for this hinge. The capacity of this hinge will largely depend on the installation and how the hinge is welded. My contact at Polar confirmed that the hinge is constructed of 1/4 inch thick steel and has a pin with a diameter of 1/2 inches. While speaking with my contact at Polar, I mentioned the...
    view full answer...
  • Is The Dump Door Hinge for Dump Trailers PLR1904-Z For The Left Or Right Hand Side?
    Hello Wanda, thanks for reaching out. The Dump Door Hinge for Dump Trailers # PLR1904-Z can be used on the left or right hand side. It is not side specific.
    view full answer...
  • Door Hinge Bracket with 4 Inch Width
    We don't have exactly what you are looking for. The # PLR1904-Z you referenced is 3-1/8 inch without the strap. The best other option is the Ramp Door Hinge - Steel # PLR1902 which utilizes as different hinge style and welds flat. It is 4 inches wide but without the bend. These are the only ramp door and dump door hinges we carry.
    view full answer...
    Image 1 for Image 2 for
  • Dimensions of Polar Steel Dump Door Hinge PLR1904-Z
    Most dimensions of the Polar Steel Dump Door Hinge # PLR1904-Z do appear on the photo from our website, which I linked for you, but I also went to our warehouse and measured the item to give two additional dimensions. These are shown on the second photo. If you need another dimension please feel free to tell me which specific measurement you need.
    view full answer...
    Image 1 for Image 2 for
  • What is the Weight Capacity of the Polar Hardware Dump Door Hinge?
    The Polar Hardware Dump Door Hinge, Steel # PLR1904-Z that you referenced does not have a weight rating according to my contact at Polar. The installation will largely dictate the weight this hinge will be able to handle. This hinge is made of 1/4 inch thick steel, so you most likely will be held to the strength of your weld on the 1 inch wide bracket. I've attached a video to help further.
    view full answer...
  • Can the Polar Door Hinge PLR1902 be Separated?
    The ends of the Polar Ramp Door Hinge # PLR1902 are actually welded on, so they cannot be separated. However, we do have a few other options available for you. The Polar Dump Door Hinge # PLR1904-Z does use a bolt to hold everything together. There is still a zerk fitting to allow everything to be lubricated. It is quite a bit different, however, so the next option may be a better option. The Redline 3/4" Greasable Hinge # HP344G can be paired with # HPN342. This could then be adapted...
    view full answer...
  • Recommended Hinges And Ramp Assist For Steel Ramp
    For your ramp, I recommend a hinge like the Ramp Door Hinge - Steel # PLR1902 or the Dump Door Hinge - Steel # PLR1904-Z. Both of these have a built in zerk grease fitting. Then you can use springs like # RS16933RH and # RS16933LH. If you want further help in lifting and lowering, I recommend the Rack'Em Double Barrel Utility Trailer Tailgate Lift Assist w/ Chain - 200 lbs # RA-27C that can be used on either side or both.
    view full answer...
  • Can Bolt of Dump Door Hinge # PLR1904-Z Be Removed
    Not super easily as it wasn't designed for that to happen regularly, but the bolt of the Dump Door Hinge # PLR1904-Z could be removed and the two pieces of the hinge could separate.
    view full answer...
  • Ramp Hinge PLR1902 For Making Swing Out Trailer Barn Doors
    The Ramp Door Hinge # PLR1902 that you referenced could swing out as far as you are needing so it would work well for you. The slide door bar lock assembly part # 305736 can also be cut down as needed as well. Then for a mechanism to lock the door open you could use a rubber socket and plunger set like the part # PLR64-66.
    view full answer...
    Image 1 for
  • Can Barn Doors of Trailer Ramp be Changed to Ramp Door
    Most likely it's possible but the level of modification you'll need to do is hard to say. We have ramp door hinge kits like the part # PLR1904-Z which you'd weld to the back of the trailer and then attach a ramp door to. But most likely you won't be able to reuse the barn doors and you'll have to come up with a ramp.
    view full answer...
  • Does Polar Hardware Dump Door Hinge, Steel # PLR1904-Z Have Weight Capacity
    The Polar Hardware Dump Door Hinge, Steel # PLR1904-Z that you referenced does not have a weight rating according to my contact at Polar. The installation will largely dictate the weight this hinge will be able to handle. This hinge is made of 1/4 inch thick steel, so you most likely will be held to the strength of your weld on the 1 inch wide bracket.
    view full answer...
  • Hinge Recommendation for Converting Gate of Dump Trailer to Barn Doors
    I recommend part # PLR1904-Z. This is a barn door hinge for dump trucks and is made of 1/4 inch steel. I don't have a drawing or install instructions I can send you, but if you take these hinges to a qualified fabricator in your area he would be would able to install them on your trailer without needing instructions.
    view full answer...
  • Replacement Hinge Recommendation for MAXXD Dump Trailer
    That's a pretty hard question to answer, but most likely the Dump Door Hinge # PLR1904-Z that you referenced would be exactly what you'd need. This hinge setup is very heavy duty and basically can be made to work on any standard dump as long as you have access to a welder.
    view full answer...
  • Recommended Replacement Hinges For Barn Doors On Dump Truck
    We do offer a hinge that may work well for you. I recommend part # PLR1904-Z. This is a barn door hinge for dump trucks and is made of 1/4 inch steel. This has a smooth surface that is designed for welding. I have also attached a photo of this hinge you can take a look at. I have also attached a photo of the four strap hinges that might work for you. As you can see, these have holes drilled in them so they can be bolted in place for both the door and the trailer. If you choose a hinge...
    view full answer...
    Image 1 for Image 2 for
  • Recommendation for Trailer Ramp Hinge that Can Handle a 500 Pound Motorcycle
    For your ramp and 500 pound motorcycle I recommend using a couple of ramp hinges, # PLR1902, sold in quantities of 1. This is a heavy duty ramp hinge and has a grease fitting so you can easily keep It lubricated. I am not sure how wide your ramp is or the available space you have to mount a hinge but the overall length of this hinge is 8-3/16. For something a little shorter we have dump door hinge # PLR1904-Z which is under 5 inches wide. I have linked videos on both of these hinges for you.
    view full answer...
  • Aluminum Hinge for a Utility Trailer Tailgate
    We do have an aluminum hinge for you. While the Dump Door Hinge, part # PLR1904-Z, only comes in steel, the Butt Hinge from Polar Hardware, part # PLR1005, is an aluminum construction. It can be welded or bolted to your tailgate. I've linked to a video review of this hinge for you to look at.
    view full answer...
  • Dimensions of the Polar Steel Dump Door Hinge PLR1904-Z
    I took a piece of the Polar Steel Dump Door Hinge # PLR1904-Z from our warehouse so that I could take a series of measurements for you. I have applied these dimensions to the linked photo, which will be added to the item's product page. Both the bracket and leaf portions are made of 1/4-inch thick steel with a raw finish. This item includes a grease zerk fitting to simplify the process of adding grease to the hinge by using a grease gun such as # L30132.
    view full answer...
    Image 1 for
  • Are The Dump Door Hinges Strong Enough To Support a Dump Tailgate Converted To Barn Style Door?
    The Dump Door Hinge # PLR1904-Z was specifically designed for heavy duty dump trailers. The mounting bracket is manufactured from 1/4" steel and the 1/2" pin can handle a lot of weight. While the manufacturer does not give a particular weight capacity due to the length of the door having as much of an effect as the weight, you would want to make sure to use a reasonable amount of hinges on your doors. Obviously a 4' tall door would need more than just 2 hinges to properly support the weight...
    view full answer...
  • Recommended Heavy Duty Hinge
    The most heavy duty hinge we have is the Dump Door Hinge for Dump Trailers item # PLR1904-Z you were looking at. This hinge is made of 1/4" thick steel, has a grease zerk fitting, and has an overall length of 5-1/4".
    view full answer...
  • Is The Dump Door Hinge for Dump Trailers # PLR1904-Z Able To Open 180 Degrees?
    The Dump Door Hinge for Dump Trailers # PLR1904-Z is capable of opening over 180 degrees. While there are no stops built into the hinge do understand that it can open less than 180 degrees depending on your door/frame and how the hinge is installed.
    view full answer...

Do you have a question about this Trailer Door Hinge?


Info for this part was:

Employee Jameson C
Expert Research:
Jameson C
Employee Adam R
Expert Research:
Adam R
Employee Cole B
Installed by:
Cole B
Employee Wilson B
Updated by:
Wilson B
Employee Mike S
Updated by:
Mike S
Employee Amanda M
Written by:
Amanda M

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