Where to Find a Replacement Key and the Number for a Master Lock Trailer Coupler Lock
Updated 01/25/2021 | Published 01/21/2021 >
Products Featured in This Question
Question:
where do I find the key number I have the package but I dont see anything that says key number
asked by: Mike K
Expert Reply:
The Master Lock Trailer Coupler Lock - 1-7/8", 2" and 2-5/16" Ball Couplers, part # ML389DAT, would not have the key number printed on the package since they put random ones in each package (printing on the package would make it easier for others to find out your key number).
As such, to determine the key number for use with # MLK1, you will need to look at the physical key itself as those are the only place where the number is printed.
If you have completely lost your set of keys (and are therefore unable to determine the key number), then your only recourse from there is to have the lock cutoff your trailer and order a new one.
I've linked to a video review of lock for you reference.
Product Page this Question was Asked From
Master Lock Trailer Coupler Lock - 1-7/8", 2" and 2-5/16" Ball Couplers
- Trailer Tongue Lock
- Surround Lock
- Universal Application Lock
- Keyed Unique
- Fits 1-7/8 Inch Ball
- Fits 2 Inch Ball
- Fits 2-5/16 Inch Ball
- Master Lock
more information >
Featured Help Information
Miscellaneous Media
Continue Researching
- Search Results: trailer tongue lock
- Search Results: utility trailer trailer jack
- Shop: Round A-Frame Trailer Jack - Topwind - 14-3/4" Travel - 2,000 lbs
- Article: The Best Trailer Tongue Locks for Preventing Trailer Theft
- Q&A: Best Weight Distribution with Sway Control for 2025 Brinkley Z Air 297
- Q&A: Anti-Rattle Device For Weight Distribution System
- Q&A: What Equalizer Upgrade Would Be Best for My 2026 Jayco Eagle 28BHU?
- Q&A: Spare Wheel/Tire Combo Recommendation for 2026 Aluma MC-10 Motorcycle Trailer
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Article: The 5 Best Trailer Drop Hitches You Can Buy
- Q&A: Availability Of 2" Long 1/2" Wheel Stud With 0.56" Spline
- Article: Trailer Tire Sizing
- Q&A: Using # 37185 Adapter to Provide 7-Way Trailer Connector on 2003 Ford Pickup
- Q&A: How Much Does The Power Mountain Tallboy 6 Ton Bottle Jack Weigh
- Article: How to Measure for Trailer Hitch Drop
- Article: How to Measure Your Trailer Wheel Bolt Pattern
- Article: Trailer Wiring Diagrams


