AEROSTAT April 2002


Protect your trailer by Glen Everett


To see the actual article with photos click here


In most cases trailers are stolen not for the contents but for the few hundred quid the thieves get for them in the local ‘free-ads’ papers. So this article looks at ways to protect your trailer.


The popular Bradley double lock with its built-in lock or long shackle padlock through a hole is easily bypassed by a thief who can simply tow away the trailer on a hook or towball that has had its rear-end ground off. This can be prevented by a lockable enclosed box around the coupling, see <>. Alternatively try a lockable device which inserts and grips into thecoupling. If you have a lockable coupling, try simply cutting the ball off an old hitch and inserting that.


Some of the more modern, larger trailers have a removable wiring lead. You could make up a replacement with all the leads connected together which, when inserted by the thief, will blow the fuses on the car as soon as the indicators, lights or brakes are used. Just remember to swap this back again before you go off!


Those of you with a fixed wiring lead can knock up a hidden switch connecting any live wires to earth body or the earth wire (white) to blow the fuse for the unknowing

If you are skilled in welding, you can weld your postcode into the chassis, especially if you don’t already have a chassis number on the trailer. An extra measure would be to paint your postcode on to the roof — a move that can also help the pilot spot when the retrieve has sneaked off for a swift half. A piece of stout chain (minimum half-inch thick links) around an immovable pillar or piece of steel buried in the ground is also a good idea.

If your wheels have holes, chain those together.


If you have room for a car battery in the trailer, try fitting a standard car alarm with a shock sensor. But be sure to securely fit the battery into a sturdy box, as you will need to take it out and charge it every couple of months, or wire it to the grey caravan socket if you have one and then you can charge it on the move.


A unique security device is the mule, permanently fitted to the trailer chassis. This clever device works like a ground anchor — spring loaded with a force of 150kg, it digs in and lifts one side of the trailer into the air if driven away. It takes just 30 seconds to deploy. Contact <> or 01257 423666.


The Tiredeflator is one of the most ingenious gadgets I have seen. It has a special replacement valve cap that screws on with an Allen key. The unit then fits over this cap and is locked in place with a built-in lock. Fitting takes 15 seconds. It takes two seconds to remove or refit. How does it work? Well, it has a weight which releases the air from the valve core when the wheel rotates. Any attempt to remove the deflator by force will damage the valve and again deflate the tyre. It deflates an average trailer tyre in about half a mile, although it took 2 miles or more for a Land Rover tyre, the exact rate being dependent on size and pressure. You just have to remember to remove it yourself before driving off. If you carry a spare, it is recommended that you use locking wheel nuts to prevent the thieves using that instead. Twin axle trailers need to use two Tiredeflators fitted on the same side, although for the price (£25) it would not harm to use as many as possible. Contact <> or Compass group on 01481 239077.


Large wire strops can be difficult to use a boltcropper on as they squash rather than cut


Wheel clamps are probably the best visual deterrent. Bulldog make some of the best industry-rated models and their DC range is specially designed for trailer-sized wheels.

A small degree of self assembly is needed the first time you use it to get the snuggest fit to your trailer but, once that is completed, it is then probably one of the fastest and easiest wheel clamps I have used. It costs around £85 but for only £10 more you can get their Norwich Union-approved Titan range, which is fiddly to fit but built like the proverbial outhouse and seems to resist everything including boltcroppers. See the website at <> or telephone

01952 728171.


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