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45" Long Side-Door Bar Lock Assembly

45" Long Side-Door Bar Lock Assembly

Item # PLR3057-45
Our Price: $118.58
Trailer Door Latch
This item qualifies for Free Shipping
Shipping Weight: 8 lbs
In Stock
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Cam-door style lock is ideal for use on trailer side doors that may be smaller than rear doors. Features 45" long pipe and rust- and corrosion-resistant zinc coating. Great Prices for the best trailer door latch from Polar Hardware. 45" Long Side-Door Bar Lock Assembly part number PLR3057-45 can be ordered online at or call 1-800-940-8924 for expert service.
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Polar Hardware Trailer Door Latch - PLR3057-45

  • Cam Door Latch
  • Latches
  • Lock Not Included
  • Polar Hardware

Cam-door style lock is ideal for use on trailer side doors that may be smaller than rear doors. Features 45" long pipe and rust- and corrosion-resistant zinc coating.


  • Cam-door style lock is ideal for use on trailer side doors that may be smaller than rear doors
  • Rust- and corrosion-resistant zinc coating
  • Mounting hardware not included
  • Overall pipe length: 45"

3057-45 Polar Hardware Side-Door Bar Lock Assembly - Zinc - 45" Long

Video of 45" Long Side-Door Bar Lock Assembly

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

Video Transcript for Polar Side-Door Bar Lock Assembly Review and Installation

Hi there, trailer owners. Today, we're going to be taking a look at Polar's side-door lock assembly. These are available in three different sizes. You can get it at 36, 45 or 55 inches long. And just like the name says, this is a locking door latch assembly. It is mostly used for the side for your smaller doors, but on some of your enclosed trailers, you may have similar styles like this at the back as well.

We just got done replacing one that was originally on this trailer that had rusted off and our nice new one is holding it nice and tight. We've got considerably more pressure. So our door's not vibrating around as much as it used to. We'll be replacing the one on the other side here as well. But we wanted to give you a comparison of how your old ones might look.And with this old style here, you can see it's all rusted up, squeaks a lot.

It's kind of difficult to move. And on the other side, well, that one, the handle came completely off. Our new one's going to be nice, smooth, and easy to operate, simply unlatch it. It also offered more pressure than our other one did, which keeps our door closed. Previously, when we had both latches shut before our handle broke off, this door would kind of rattle around.

It really didn't stay very well shut with even just the new one on the one side, it's significantly stronger and feels more secure and shut. It offers a steel construction. So it's going to be solid and durable and to prevent rust and corrosion like our old one's had. It has a zinc plating on it, which is going to keep all that moisture off and give us a nice finish over it that's going to last a long time and they're also a fairly standard size.When we replace this one, our bar here was able to line right back up with the existing holes. It doesn't come with hardware, so you will need to reuse your old hardware or purchase new hardware if you want it to be nice and shiny.

I do highly recommend carriage bolts if you are replacing the hardware so that way it has a nice button look appearance. And when you go to tighten down the nut on the other side, it's being held out here. It also comes with a new lock side for your handle. It's got a nice, smooth pivot and holes in both the top and bottom. So you can put a padlock through when you've got it all latched and closed so nobody can get inside. It's a pretty straightforward and simple installation.In most cases, you won't have to do any drilling, but sometimes you will if there's a slight difference on yours. We're going to go ahead and show you how to install it now. One of the things you might consider, if you've got a enclosed trailer that you want to keep out, any moisture and stuff, maybe like a side door on a toy hauler or something. You may want to put some silicone or seal it on the backside of this to keep out any moisture. So you can see why we're going to be replacing our old one here. Rust has got the better of it. We're going to go ahead and take our old assembly off here and put a whole new assembly on. It doesn't come with new hardware so we will be reusing our old bolts and they come as a quantity of one.So we're going to go ahead and get two of them and replace both sides. That way we'll have a matching look here at the back of our trailer. And we don't have to worry about this happening to the other side as well. We're now here on the inside of our trailer, where we can see our hardware here. On some of your trailers you may have a trim piece here that you need to remove. Ours doesn't have any kind of enclosure on it, covering it up. And we're just going to remove these carriage bolts. There's a nut on that we're going to take off on each one and we're going to use a 1/2 inch socket to do so.And then we can just slide it off of here. And it's not a bad idea just to clean up the area behind where your old ones were, we're just using a little bit of alcohol to clean it up, but you could use soap and water and a brush, just like you clean your car. We can now take our new one and put it in place. We want to make sure that the hinge here is on the outside and we're going to just take our carriage bolt, slide it through and then slide it through here. You want to make sure that you're using carriage bolts because you see the holes here are cut out in a square. That way you don't have to hold it while you're tightening it down. And just put a few turns on it, you don't need to go crazy. It's just going to make, installing the rest of our hardware a lot easier if we don't have to hold it up.From here, we can just install the rest of our bolts by lining up the holes again and reinstalling the hardware. We can then go back and tighten our bolts down. So we're just going to take these off on the backside. Ours are nuts that have Torx bit openings in them, and we're going to use a T55 Torx for ours, but yours could potentially be something else. Now, the assembly might get a little stuck in there, that's no big deal. We can just knock it through with our hammer and an easy way to ensure you don't damage the threads. Now I know this is an old one, so we're not going to be reusing it anyway. We can thread our nuts on there, and that usually is enough to help us tap it, just to kind of get it started.We can likely now just go to the other side and pull the assembly office. We've made a little gap between the door and the latch assembly. So now we can easily just kind of work it out. If you have a lot of rust and stuff on here, sometimes it's easier to use an abrasive pad to remove the material rather than some alcohol on a cloth. So now we've got our new latch assembly and I went ahead and checked it with our old one and unfortunately our bolt holes aren't going to line up on this one. So we are going to have to drill a new hole for our new latch. So an easy way to ensure that it's going to line up properly we're just going to put it on our bar, push it in place.And then we're going to try to use one of the old holes as a template if we can. Looks like it's going to line up pretty good with that bottom hole. So since it's going to line up with our bottom hole, just fine, we're going to go ahead and use that bottom hole. Then we'll just set this thing up straight after running it through and use the top hole as a template. So I've gone ahead and just slid the bolt in. I didn't tighten it down yet. We're just using it again as a template. So we're going to line this up right below our other hole. And then we're going to go ahead and make a little pilot mark.We can move our bracket out of the way, and then just finish drilling this out. We're using a 5/16 drill bit. Once you get your top field out, we're just going to put that back in place. You don't want to put your lock assembly on it and slide your carriage bolt through. And we're going to walk around to the other side, to install our nuts onto our bolts. Here on the other side, we're just going to start our nuts, trying to be careful not to push the hardware back through. And then we can just tighten them back down.Now that we've got it tightened down and installed, let's go make sure that it's going to work properly. We've got a good tension on our door it's going to hold it shut, and our latch works properly. And you might be wondering what we're going to do about this hole here. And you've got a couple of options. You could run a nut in a bolt through it, but it looks like that's going to interfere with our latch mechanism. So we're just going to be filling it up with some silicone. You can get black silicone here at if you think you're going to need some. And we're just going to seal that up. You can also fill in the inside if you want to ensure that you're completely sealed. And that completes our look at the Polar side-door bar lock assemblies.

Customer Satisfaction Score:

Customer Reviews

45" Long Side-Door Bar Lock Assembly - PLR3057-45

Average Customer Rating:  4.8 out of 5 stars   (41 Customer Reviews)

Cam-door style lock is ideal for use on trailer side doors that may be smaller than rear doors. Features 45" long pipe and rust- and corrosion-resistant zinc coating.


Ordered item 4/19. Item shown as in stock ready to ship.
Receive email several days later showing item will ship on 5/2 and arrive 5/9 ?? Despite being in stock??
Spoke to representative regarding wait time of 3+ weeks despite item listed as ready to ship,,,item arrived 4/30.
Package was damaged with item protruding out side of box.
No paperwork or invoice in box.
Item fit as promised.
Not sure if I would purchase again, item was as described but waiting 3weeks for item that was in stock to ship and damaged box was disappointing.


Part I ordered was perfect and exactly what I ordered, billing was fast as well as the shipping,thanks for the great price and service, will definitely buy more in the future.

I purchased this for my service truck rear door and it worked perfectly and still is. This is a great product and has held up without any issues
James b - 12/18/2022


I needed a better way to secure my trailer door. This worked perfectly and was easy to install. I recommend it for all trailer doors.


perfect replacement and 1,000 lbs stronger than original for less. advice I'd offer is to determine if you need a top or side winder, your trucks tail gate will appreciate you :)


thank you for the fast service, Quinn was a big help in this process.


Fast service. Good product


By far the best service and communication, I personally do business with over two dozen companies a month, and recently customer service has been at all time low. But I am extremely Encouraged by the quality of service of Thank you for the quality.


Parts arrived in great shape. Great packaging. The best thing was working with Odelia K. She is absolutely a great asset to your customer service department. I was looking for specific side door bar lock assembles to replace my current ones. I did not want to drill new (more) holes in my trailer. Odelia contacted your supplier and got the actual prints for the parts for me to review. By doing this I could verify that the bolt hole center spacing was exactly like the bars I was replacing. Odelia made great follow up calls back to me and was always friendly and very pleasant. In today's world with customer service almost non existent in a lot of company's she is a gem.


This is the second set of trailer latches I have purchased recently. The latches from etrailer seem to be of better quality than the first set from another on-line company.
Great product!


had to create some aluminum shims for behind the latch hinges for my door configuration but went on great, works great, door is more secure.


These door lock assemblies are great. I do have to adjust the boly locations by reaming the holes to match up with my old lock assemblies, but lust minor adjustments for a perfect fit.


Perfect Fit to Replace some old Rusted out handles.
Very easy to install. and fast shipping shipped the night I ordered.


Everything arrived on time & was exactly what we were looking for. Only thing that would've made this purchase even better is if bolts were included in the assembly.


A perfect fit


Great service. Description of part was clear so ordering was easy. Fast damage free delivery


Delivered promptly and fit perfectly!


Everything I ordered came to me as promised. Even though the product was back ordered the company kept me informed.


The part came quickly, and looks good. Will work for me. I will tell people about you guys, and will use you again thanks!



Have installed a lot of them






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Info for this part was:

Employee Lindsey S
Edited by:
Lindsey S
Employee Jameson C
Expert Research:
Jameson C
Employee Dustin K
Video Edited:
Dustin K
Employee David F
Installed by:
David F
Employee Kristina F
Written by:
Kristina F

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