A caravan sitting unhitched in your driveway, at a storage yard, or parked at a campsite is an easy target. Someone with the right gear can hitch up and drive away in minutes. Wheel clamps and hitch locks are your first line of physical defence: they stop your van from being towed, rolled, or hitched without your say-so.
Neither device is foolproof on its own. A determined thief with an angle grinder can defeat most locks given enough time. But that’s the point: you’re buying time and creating noise, attention, and hassle. Most caravan theft is opportunistic, and a visible, high-quality clamp or lock sends a clear message that this van isn’t worth the effort.
This guide covers everything you need to know about choosing the right wheel clamp and hitch lock for your setup, including which products are worth your money and which coupling types need specific locks.
What To Look For
Not all locks and clamps are created equal. Here’s what actually matters when you’re choosing.
Material & Construction
Hardened steel or composite steel construction is non-negotiable. Cheap pot-metal locks from marketplace sellers might look the part, but they can be cut through with basic hand tools in seconds. Look for locks made from 304 stainless steel (Kovix) or hardened composite steel (Purpleline, Milenco). If the listing doesn’t mention the material, that tells you something.
Lock Mechanism
The lock barrel itself matters as much as the body. A 7-pin cylinder lock (used by Purpleline) resists picking, drilling, and freezing. Kovix uses a double-locking pin system with anti-drill properties. Avoid anything with a standard padlock shackle unless the padlock itself is high-security rated.
Coupling Compatibility
This is where people get caught out. A hitch lock designed for standard 50mm ball couplings won’t fit a DO35 or Treg poly block hitch. Check your coupling type before buying. If you’re running a Cruisemaster DO35 or DO45, you’ll need a coupling-specific lock (covered below).
Visibility
High-visibility colours (yellow, orange, red) serve a genuine purpose. A bright yellow wheel clamp screams “this van is protected” from across a car park. It’s a psychological deterrent before anyone even touches your van. Purpleline has made high-vis a core part of their design philosophy, and it works.
Keyed-Alike Systems
If you’re buying both a wheel clamp and hitch lock, look for keyed-alike options. Purpleline offers complete security kits where the clamp and lock share the same key, which means one key for everything instead of fumbling through a keyring. It’s a small thing, but after your hundredth setup and packdown, you’ll appreciate it.
Check your caravan insurance policy. Some insurers require a wheel clamp or hitch lock to be fitted whenever the van is unhitched, and some offer premium discounts for approved security devices. It could pay for itself.
Hitch Locks
A hitch lock prevents someone from coupling your caravan to a tow vehicle and driving away. It’s the fastest, lightest security measure you can fit, and most take less than 30 seconds to install. Every caravan should have one as a bare minimum.
The four brands dominating the Australian caravan hitch lock market are Purpleline, Kovix, Milenco, and AL-KO. Each takes a slightly different approach.
✔ Pros
- Built-in 120dB alarm is a serious deterrent
- Fits multiple coupling types including DO35
- IP67 waterproof, rust-resistant
- Alarm can be switched on or off
✗ Cons
- Higher price than non-alarmed options
- Lithium battery needs occasional replacement
- Bulkier than simple pin-style locks
✔ Pros
- Excellent price for quality build
- Chain lock feature secures safety chains too
- Keyed alike with other Purpleline products
- Compact, easy to store
✗ Cons
- 50mm ball couplings only (no DO35)
- No alarm function
✔ Pros
- Solid build quality from a trusted brand
- Variable height setting for different couplings
- Comes with storage case
- Compact and lightweight
✗ Cons
- Pricier than the Saracen for a non-alarmed lock
- Not keyed alike with other brands
Other Hitch Lock Options
The AL-KO Universal Coupling Lock (~$65-110) is a straightforward, no-frills option that works well with AL-KO chassis couplings and most other standard Australian hitches. If your van runs an AL-KO chassis (and many do), it’s worth considering for the guaranteed compatibility. Check price at CARAC →
The Kovix Hitch Pin Lock (~$50) is the simplest option: it secures your receiver hitch pin so the coupling can’t be removed from the towbar. It won’t stop someone unhitching the coupling itself, but it adds a layer at the receiver end and it’s compact enough to live permanently in your glovebox. Check price at Supercheap Auto →
Coupling-Specific Locks
If your caravan or camper trailer runs an off-road coupling like a Cruisemaster DO35, DO45, or a Gen Y hitch, standard hitch locks won’t fit properly. You need a purpose-built lock designed for your specific coupling.
Cruisemaster DO35/DO45 Bi-Lock
The Cruisemaster Bi-Lock is purpose-built for DO35 and DO45 V1 couplings. A steel dummy pin drops into the universal joint from the top, and a keyed lock secures it from the bottom. With the lock in place, the coupling is completely inoperable. It’s compact, well-made, and designed by the same company that manufactures the coupling, so the fit is precise. Around $105-120.
The Gen 2 Bi-Lock fits DO35 V2, V3, V3Plus, and DO45 V1. It does not fit the DO45Plus, which needs a separate lock. Check your coupling version before ordering.
Check price at Supercheap Auto →
Gen Y Infinite Rule Hitch Locking Pin
If you’re running a Gen Y hitch system, their own locking pin replaces the standard pin with a keyed locking version. Purpose-built to fit the Gen Y receiver. Around $40-60.
A hitch lock only secures the coupling point. It doesn’t stop someone chaining up to the chassis and dragging, or winching your van onto a tilt tray. For proper protection, combine a hitch lock with a wheel clamp and, ideally, a GPS tracker or alarm system.
Jockey Wheel Locks
An often-overlooked addition. A jockey wheel lock prevents anyone from winding the jockey wheel up, which they’d need to do before hitching and towing away. Used alongside a hitch lock, it adds another step a thief has to defeat, and that’s the whole game: layers of inconvenience.
The Black Jack Jockey Wheel Lock (~$30-50) fits over the jockey wheel handle and prevents it from being wound. Compact and affordable. Check price at CARAC →
The Trail-A-Mate Anti-Theft Tow Hitch Trailer Lock (~$30-50) is a dual-purpose option that locks the jockey wheel mechanism. Suits most standard configurations. Check price at Repco →
Wheel Clamps
A wheel clamp physically stops the wheel from rotating. Even if a thief defeats your hitch lock and manages to couple up, a clamped wheel means the van isn’t going anywhere without making a serious scene. Wheel clamps are also the most visible deterrent in your arsenal: a bright yellow clamp on your wheel tells everyone within eyeshot that this van is locked down.
There are two main styles: full wheel clamps that wrap around the tyre and cover the wheel nuts (preventing wheel removal), and receiver-bolt clamps that bolt through a wheel nut for a faster fit. Both work, but the full-coverage style offers better protection since the thief can’t simply unbolt the wheel and swap it for a spare.
✔ Pros
- Quick-fit receiver nut system
- Covers wheel nuts to prevent removal
- Anti-pick, anti-drill, anti-freeze lock
- High-visibility design
✗ Cons
- Premium price point
- Heavier than budget clamps
✔ Pros
- Proven track record, widely trusted
- Covers wheel nuts to prevent removal
- Fits on-road and off-road wheels
- Slightly cheaper than the Pro
✗ Cons
- Slower to fit than the Pro model
- Two-piece design takes a moment to align
✔ Pros
- Lighter and easier to store than competitors
- Simple wind-on fitting
- Foam strip protects rims
- Good price for a quality clamp
✗ Cons
- Doesn’t cover wheel nuts (wheel could be swapped)
- 16″ max wheel size limits compatibility
More Wheel Clamp Options
The Purpleline Samurai (~$250-275) is a slightly more compact Purpleline option with the same 7-pin lock mechanism. Fits tyres up to 275R17. A good choice if you want Purpleline quality but prefer something lighter and easier to store. Check price at Caravan RV Camping →
The Purpleline Gemini Dual Axle Wheel Lock (~$320-350) is designed specifically for tandem-axle vans. It welds both wheels together using two high-security locks, immobilising both wheels in one hit. If you’ve got a tandem, this is the one. Check price at Caravan RV Camping →
The Aussie Traveller Deluxe Wheel Clamp is a solid mid-range option from a well-known Australian brand, worth considering if you’re on a tighter budget. Check price at Caravan RV Camping →
The Klamp It Wheel Clamp (Type C) is another available option. Check compatibility with your wheel size before purchasing. Check price at Caravan RV Camping →
Combo Kits: The Smart Buy
If you’re buying both a hitch lock and wheel clamp (and you should), the Purpleline FullStop Off-Road Complete Security Kit bundles a Samurai Wheel Clamp with a Saracen Off-Road Hitch Lock. Both are keyed alike, so one key does everything. They come in a slim carry bag for easy storage. This is the kit designed for off-road setups running DO35-style articulated hitches. Around $280-310.
For standard 50mm ball coupling setups, look at the Purpleline Anti-Theft Pack (CSK100) which pairs the Samurai with the standard Saracen hitch lock.
Check price for the Off-Road Kit at Caravan RV Camping →
When storing your wheel clamp in the van, keep it near the door rather than buried under gear. If it takes 10 minutes to dig out, you’ll stop using it. Make it part of your unhitch routine: handbrake on, wheel chocks down, clamp on.
Quick Comparison
| Product | Type | Price | Key Feature | Best For |
|---|---|---|---|---|
| Purpleline Nemesis Pro Best Pick | Wheel Clamp | ~$290 | Quick-fit, covers wheel nuts | Most caravans |
| Purpleline Nemesis | Wheel Clamp | ~$270 | Hardened steel, 7-pin lock | Best all-rounder |
| Purpleline Gemini | Wheel Clamp | ~$330 | Locks both wheels together | Tandem-axle vans |
| Milenco Australian Budget Pick | Wheel Clamp | ~$240 | Lightweight, wind-on fit | Budget-conscious |
| Kovix KTR-18 Best Pick | Hitch Lock | ~$225 | 120dB alarm, fits DO35 | Alarmed hitch security |
| Purpleline Saracen V2 Budget Pick | Hitch Lock | ~$100 | Chain lock, hardened steel | 50mm ball couplings |
| Milenco Hitchlock | Hitch Lock | ~$150 | Storage case, variable height | Quality + portability |
| Cruisemaster Bi-Lock | Coupling Lock | ~$110 | Purpose-built for DO35 | DO35/DO45 owners |
| FullStop Off-Road Kit Best Combo | Kit | ~$295 | Clamp + lock, keyed alike | Best value bundle |
The Verdict
Every caravan should have, at minimum, a hitch lock and a wheel clamp. They’re relatively inexpensive for the protection they provide, and they’re one of the few security measures that work as both a physical barrier and a visual deterrent.
For most Big Lappers, the Purpleline FullStop Off-Road Complete Security Kit is the smartest buy. You get a quality wheel clamp and hitch lock in one keyed-alike package, and Purpleline’s build quality and lock mechanisms are proven. If your budget allows, upgrade to the Nemesis Pro wheel clamp for even faster fitting.
If you want the added peace of mind of an alarm built into your hitch lock, the Kovix KTR-18 is excellent. That 120dB siren going off at 2am will ruin any thief’s evening. Pair it with a Purpleline wheel clamp for a seriously robust setup.
Running a DO35 or DO45 coupling? The Cruisemaster Bi-Lock is a must. It’s made by the coupling manufacturer, fits perfectly, and at around $110 it’s cheap insurance.
And remember: wheel clamps and hitch locks are your first layer, not your only layer. For comprehensive security, combine them with a GPS tracker and an alarm system.
- Always use both a hitch lock and a wheel clamp when your van is unhitched
- Match the lock to your coupling type: standard 50mm ball, DO35, or Gen Y
- Buy quality: hardened steel and anti-pick locks are worth the extra spend
- High-visibility designs are a genuine deterrent, not just marketing
- Combo kits (like the Purpleline FullStop) save money and give you keyed-alike convenience
- Check your insurance policy: a wheel clamp or hitch lock may be a requirement or earn a discount
Comment (0)