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Trimax King Pin Lock for 5th Wheel Trailers - Collar Style - Hardened Alloy - Yellow
Trimax Locks

Trimax King Pin Lock for 5th Wheel Trailers - Collar Style - Hardened Alloy - Yellow

Part Number: TMX56RR
In Stock
$52.04
Retail:$94.99
You Save: 45%
King Pin Locks
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Secure your fifth-wheel camper or utility trailer with this heavy-duty, hardened alloy king pin lock. Fits over your trailer's king pin to prevent towaway theft. Full collar keeps your hands grease-free during installation. Fastest Shipping and Great prices for Trimax King Pin Lock for 5th Wheel Trailers - Collar Style - Hardened Alloy - Yellow. Read our customer reviews of Trimax Locks king pin locks. Call 1-800-940-8924 for expert service or order your king pin locks part number TMX56RR by Trimax Locks online at etrailer.com.
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  • Reviews (107)
  • Q & A (0)
  • Photos

Trimax Locks King Pin Locks - TMX56RR

  • Steel
  • Keyed Unique
  • Trimax Locks
  • Yellow

Secure your fifth-wheel camper or utility trailer with this heavy-duty, hardened alloy king pin lock. Fits over your trailer's king pin to prevent towaway theft. Full collar keeps your hands grease-free during installation.


Features:

  • Lock secures your 5th-wheel trailer by preventing hookup
  • Fast, easy, clean installation
    • Full collar design keeps your hands clean as you slide lock over king pin
    • Push-button lock activates without key needing to be inserted
  • Yellow color lets would-be thieves know your trailer's locked from a distance
  • Durable hardened alloy construction
  • Epoxy powder coat resists corrosion
  • Tube key lock cylinder provides better security than standard key mechanisms
    • Harder to pick and resists drilling
    • More difficult to duplicate keys
  • 2 Keys included


Specs:

  • Application: standard 2" diameter king pins
  • Overall dimensions: 2-3/4" tall x 4" wide
  • Inner diameter: 2-7/8"
  • Limited lifetime warranty


TFW60 Trimax Locks Heavy Duty Solid Alloy 5th Wheel King Pin Lock





Customer Satisfaction Score:

Ratings & Reviews

4.6

107 reviews
Review sort icon
Secure your fifth-wheel camper or utility trailer with this heavy-duty, hardened alloy king pin lock. Fits over your trailer's king pin to prevent towaway theft. Full collar keeps your hands grease-free during installation.

by:



by:

Great product for a good price. Won’t stop a thief with a cutting torch, but it will send the average thief to another RV!



by:

It was exactly what I ordered it works great thanks



by:

great deal



by:

Fits great. Works great. Seems to be pretty tough.



by:

Good service and easy to order in order was on time. Thank you so much appreciate it.



by:

This lock is easy to use and a great visual deterrent. I don't know if it would stand up to a determined thief with time tools and a hidden location. But, for a trailer in a somewhat secure location it seems like it will serve well.

Jason profile picture

Jason

12/5/2023

After a year I am happy with this lock. It is easy to use and a good visual deterrent. Will it stop everyone? Nope, but it is solid and bright yellow. It says move to the next trailer.



by:

It does exactly what it's supposed to do. It is substantial and provides the additional security I need.



by:

I had to glue the lock in do to it falling out.



by:

I have not opened the box yet but I was thinking the kingpin lock would be heavier weight.



by:

Excellent pin lock rust proof and easy to use thx etrailer



by:

as usual, ease in finding, ordering and fast delevry.



by:

The fit is great for protection of the 5th wheel trailer from anyone other than myself that may want to borrow the coach.



by:

Lightweight and easy to use. The bright yellow color will make it easy to find in my storage compartment.



by:

This isn't going to deter the thief with an acetylene torch or a master barrel key, but it will stop that boondox "theft of opportunity".
As capable as locks costing much more.
Extremely visible!



by:

We purchased this to replace an aging pin lock that is more difficult to attach. We like the bright color, making this much more obvious. The lock is based on a solid steel pin about 3/8" in diameter that extends over the bottom collar of the pin. As long as it is truly made of hardened steel, it should be enough of a deterrent to a would-be thief.



by:

Great quality product at a reasonable price. Easy install and very effective pin hitch lock .. would buy again



by:

This is great! I purchased this because it is a completely round. This way the grease from the kingpin stays inside the lock. So no mess!



by:

Very easy and secure

Greg profile picture

Greg

1/9/2026

Awesome as it should

Gwendolyn Y. profile picture
Etrailer Expert

Gwendolyn Y.

1/9/2026

@Greg Glad to hear the Trimax lock is keeping your 5th wheel safe!


by:

Looks like a good product, but I will have to adjust since it won't completely slide on the 5th wheel pin, and latch.

Gwendolyn Y. profile picture
Etrailer Expert

Gwendolyn Y.

7/15/2025

That sounds frustrating. We haven't ran into any fitment issues so I'm curious to know what brand of king pin that's on your camper. Let me know when you have some time, David.



by:

It nice to be able to lock the king pin without getting grease all over your hand.



by:

Overall I am really satisfied with the lock, it is nice and sturdy. As a few others have reported the upper part of the collar was about 10 thousandths of an inch to small to fit over the upper part of the king pin. I got out the Dremel an sanded the inside of the collar and it fits like a charm now.



by:

"Heavy Duty Solid Steel 5th Wheel King Pin Lock", not a chance! I put a magnet on the body of the collar, no signs of any steel! Best guess is the body is maybe aluminum. The only steel is the inner cylinder of the keyed lock. Anyone with a hammer could defeat this collared lock. Now I have to figure a way to send this garbage back and get my money back.



by:

Doesn't fit. Goes on easily over the bottom of the kingpin, but jams when trying to push onto the top of the kingpin. Have to push on fully to activate the lock. It rocks indicating the lock isn't perfectly round as the rock moves with the lock when I rotated to determine why it wouldn't fit. Sanded off the paint on the king pin and inside the lock. Need to pound on and remove with a crowbar. The fifth wheel was standard on my camper. would expect it to fit as they showed in the video's. Have to see about sending back.

Jenny N. profile picture

Jenny N.

7/10/2023

I am sorry that the lock is not working out for you. Would you be able to send a picture showing how it fits on your king pin.

Steve profile picture

Steve

7/17/2023

@JennyN Here are pictures of the king pin. The I.D. of the lock is 2 7/8” and the O.D. Of the king pin is 1/64” over 2 7/8” resulting in the pound in pry off. The 5th wheel came with the camper. It is an Artic Dox 27-5.
Jenny N. profile picture

Jenny N.

7/26/2023

@Steve I reached out to the manufacturer and they agree that it is not working like it should. It should be fitting with your king pin lock. I will have our Customer Service team reach out to you.


by:

Does not fit on the king pin of a Curt Rotoflex pin box. Inside diameter is too small to fit of over the upper part of pin.


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See what our Experts say about this Trimax Locks King Pin Locks

  • King Pin Locks Compatible With PullRite Superglide Capture Plates
    The Trimax King Pin Lock # TMX56RR can still be used with your 5th wheel having a capture plate from PullRite. The capture plate mounts to the top of the kingpin and only takes up a similar amount of space that a Lube Plate # RP83002 would. If you happen to have one of the few capture plates which also has a funnel type block welded near the king pin you would want to consider a lock like the etrailer # e98896 as it does not have the section which slides over the top of the king pin channel.
    view full answer...
  • What is the Difference Between the Red and Yellow Trimax King Pin Locks?
    Hey Tom! The Red Trimax King Pin Lock # TMX36RR and the Yellow Lock # TMX56RR are literally the same lock, just with different colors. I'm not sure why there's a price difference like that, but usually I tell people to take advantage of the lower price while you can. What drew you to this king pin lock?
    view full answer...
  • Locks Available For A Gooseneck Trailer
    Hi Alvin! There are a couple ways to lock a gooseneck trailer, but not as many as other styles. If it will fit, I am a fan of the Blaylock EZ Lock Gooseneck Coupler Lock # BLTL-50-40D. It's easy to install and is American made. The only thing is, it is designed to fit Bulldog, Stallion, Superior, and T.E.M. Gooseneck Couplers. There are instances where it fit other things as well, but if you take a look at the picture I included, you can get a good idea of if it will fit your trailer...
    view full answer...
  • Recommended King Pin Lock For a 5TH Wheel Caming Trailer
    I recommend the Trimax King Pin Lock for 5th Wheel Trailers in Red # TMX36RR or Yellow # TMX56RR. The bright colors allow you to easily see it is in place and helps to deter would be thieves. They both have a tamper resistant lock and fully incase the king pin. For extra protection the Red # TMX36RR lock uses a hardened steel that is more durable and will not cut as easy as the Yellow # TMX56RR.
    view full answer...
  • Trimax King Pin Lock TMX56RR Does Not Fit - What Lock Is Recommended Instead?
    Since the Trimax # TMX56RR did not fit, I recommend taking a look at the etrailer 5th Wheel King Pin Lock # e98896. I like this lock because it is designed to be universal, and will fit virtually any pin box with a standard kingpin. The collar of the lock is 1-1/2" tall, which allows for a secure fit, even on Pin boxes like the Morryde RPB72-FD where space may be limited. These locks can also be keyed alike, if you want to order multiple locks that use the same key.
    view full answer...
  • Troubleshooting Unlocking the Trimax King Pin Lock
    Sometimes keys won't fully seat into the lock core (from our experience with the various locks we carry) and so I recommend taking a rubber mallet and lightly tapping the inserted key to see if that helps seat everything properly so you can unlock your Trimax King Pin Lock # TMX56RR. You also might try some dry lock lube to help loosen up the core if it is seizing on you. When I reached out to my contact at Trimax they also asked if the keyhole is lining up to the left at 9 o'clock so...
    view full answer...

Do you have a question about this King Pin Lock?


Info for this part was:

Employee Lindsey S
Edited by:
Lindsey S
Employee Jeff D
Installed by:
Jeff D
Employee Ed W
Installed by:
Ed W
Employee Kurt W
Installed by:
Kurt W
Employee Joshua S
Video Edited:
Joshua S
Employee Dustin K
Video Edited:
Dustin K
Employee Wilson B
Updated by:
Wilson B
Employee Sabrina W
Written by:
Sabrina W
Employee Daniel D
Video by:
Daniel D
Employee Evan R
Video by:
Evan R

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