Heavy-Duty Trailer Hitch Locks
Our top picks
Master Lock 2866DAT
Fits 1/2 and 5/8 in receivers.
About $19 (masterlock.com list)
Check price at Master Lock ↗Trimax TS32
Fits 1/2 and 5/8 in with sleeve.
Check current price
Check price at Trimax ↗AMPLock
Custom-fit range for many coupler types.
Check current price
Check price at AMPLock ↗
Comparison
| Lock | Best for | Fits | Price (approx.) | |
|---|---|---|---|---|
| Master Lock 2866DAT | Best Class III/IV value | 1/2 in and 5/8 in receivers; 2-3/4 in usable pin length | About $19 (masterlock.com list) | Check price ↗ |
| Trimax TS32 | Best universal (stainless option) | 1/2 in and 5/8 in receivers (with sleeve) | Check current price | Check price ↗ |
| AMPLock (coupler, gooseneck, kingpin, hitch, latch pin, door locks) | Best heavy-duty hitch locks | Coupler (boat, RV, cargo), gooseneck (Bulldog, Atwood), kingpin, hitch 1-1/4 to 3 in, latch pin, barn/roll-up door | Check current price | Check price ↗ |
| Proven Industries Model 2516 | Best heavy-duty coupler lock | Most 2-5/16 in trigger- and thumb-latch couplers | About $250 (provenlocks.com list) | Check price ↗ |
How we chose: picks are based on published specifications, materials, fit charts, manufacturer information and patterns in owner reports. We have not lab-tested these locks. Prices are approximate list prices seen on maker sites in October 2026 and change often.
Our picks in detail
Master Lock 2866DAT
Who it is for: Most trucks with 1-1/4 or 2 in receivers.
- Fits 1/2 and 5/8 in receivers
- Rated up to Class III/IV, 10,000 lb (5/8 in)
- Weather seal and cap
- Only protects the hitch, not an unhitched trailer
- 2-3/4 in span too short for some receivers
- Type: Receiver hitch pin lock
- Fits: 1/2 in and 5/8 in receivers; 2-3/4 in usable pin length
- Build: Swivel head, push-to-lock, weather seal and cap, 4-pin cylinder
- Keyed alike: K1 key blank
- Price: About $19 (masterlock.com list)
5/8 in pin rated Class III/IV, 10,000 lb; 1/2 in Class I/II, 3,500 lb.
Check price at Master Lock ↗Trimax TS32
Who it is for: Owners with more than one receiver size.
- Fits 1/2 and 5/8 in with sleeve
- Stainless version available
- Keyed-alike sets
- Price not confirmed on our check
- Type: Universal receiver lock
- Fits: 1/2 in and 5/8 in receivers (with sleeve)
- Build: Steel; stainless SXTS32 version available
- Keyed alike: Keyed-alike sets available
- Price: Check current price
Trimax T5 pin (5/8 in, 3-1/2 in span) fits Class V hitches.
Check price at Trimax ↗AMPLock (coupler, gooseneck, kingpin, hitch, latch pin, door locks)
Who it is for: Owners who want custom-fit security and a fit-finder.
- Custom-fit range for many coupler types
- 5-year warranty with registration
- Fit quiz on maker site
- Prices not confirmed on our check
- Heavy
- Type: Custom-fit lock range
- Fits: Coupler (boat, RV, cargo), gooseneck (Bulldog, Atwood), kingpin, hitch 1-1/4 to 3 in, latch pin, barn/roll-up door
- Build: Heavy-duty steel, custom-fit; fit quiz on site
- Keyed alike: Check per model
- Price: Check current price
5-year warranty with registration (per maker).
Check price at AMPLock ↗Proven Industries Model 2516
Who it is for: Owners of valuable 2-5/16 in trailers stored unattended.
- Custom fit wraps the coupler, little room for tools
- 1/4 in steel, tubular key
- Keyed-alike option across the range
- Can capture most safety chain hooks
- Expensive
- Must match your exact coupler model
- Heavy
- Type: Coupler lock (custom-fit)
- Fits: Most 2-5/16 in trigger- and thumb-latch couplers
- Build: 1/4 in steel, black powder coat, puck lock, 7-pin tubular key
- Keyed alike: Yes (keyed-alike option across Proven line)
- Price: About $250 (provenlocks.com list)
Can secure most 5/16 in safety chain hooks per maker; check the fit index for your coupler.
Check price at Proven ↗Ratings matter
A hitch pin lock is a load-bearing part while you tow. Match or exceed your hitch class and gross trailer weight. Do not use an unrated lock as a towing pin.
Heavy-duty features
- Forged or hardened steel; stainless if exposed to salt.
- Correct span for wide receivers.
- Anti-rattle or sleeve options.
- Shrouded or protected cylinders.
Our pick
Master Lock 2866DAT: best class iii/iv value. Most trucks with 1-1/4 or 2 in receivers. If budget matters more, see the other picks above.
Check price at Master Lock ↗FAQs
- What is the strongest hitch lock?
- Look for hardened or stainless steel and a rating that exceeds your towing load; heavy-duty brands publish ratings.
- Can I tow with a locking hitch pin?
- Yes, if it is rated for your hitch class.