Jeff I have never had an issue while traveling, but heard of storage lot issues. Personally I don't have one. But I do have a hidden power kill switch. There are a few thread here, Google king pin locks
Examples
https://www.etrailer.com/dept-pg-King_Pin_Locks.aspx
https://www.amazon.com/s?k=King+pin+...f=nb_sb_noss_1
https://www.blueox.com/product/bx883...king-pin-lock/

Hope this helps

The problem is primarily unattended storage. The intent is to make your unit more difficult to move than the next one. All stabilizers down and power shut off is a good plan. I do have a pin lock like the ETrailer link provided by Keith as one more level of difficulty.

Rob

One of the best theft deterrents I've seen is a home made assembly using a 1 1/4" pipe running side to side through corresponding spokes of the wheels. It was kind of like a long bolt running across the trailer through the wheels. A 3" diameter plate was welded on one end, and a hole for a lock on the other end. The lock was enclosed in a cup of about 4" I.D. pipe so it could not be cut or hit with a hammer.

Obviously once the trailer started moving the pipe would move with the wheel and catch on the springs and prevent further travel. Theft would require removing the 2 wheels but would be difficult if pipe were built to tight specs.

Jeff - we have a custom designed and built by the original owner of our 303 as shown in these pictures.

Dan

There is another way that could be considered a multitasker. Most of our wheel rims have spoke openings, get Grade 100 chain and a hardened lock of a size the will just fit through the wheels and loop and lock them together. When camped you can also use it to lock up things like a generator, etc. At a storage place I used a long time ago they let folks loop chains around the fence posts and through a bumper, etc We had a small TT at that time. The weak link is usually a lock that can be cut with bolt cutters. That is the one place not to skimp and HD or Lowe's don't normally carry the good stuff. Brands, just like trucks, everyone has thier favorites. Look for testing reviews. ABUS , Stronghold, Master Lock high end, and others..!00 grade chain is the strongest grade, but I have seen a 110, but that grade is not apart of the standardize grading. Now if you do get a king pin lock, I like the ones that hide the padlock making it impossible to get a bolt cutter on them.

Keith

I use this one. Not perfect but a deterrent as mentioned above. It also is a good bright alert that you might be close to hitting your head.

​​​​​​https://www.amazon.com/BOYISEN-Conta...NsaWNrPXRydWU=

Thank you everyone for the replies. It makes sense now and I really like the idea of a chain thru the tires. I have property where I'm going to be parked when I am not out on the road so no worries with extended storage. I may get a pin down the road just as an added precaution but it sounds like a kill switch and a chain would be the cheapest and easiest for now.

I use this (a previous model). I'd rather have something that is obvious to a thief before they make an attempt.

5th Wheel Lock Model PL-5 – Proven Industries (provenlocks.com)
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