Sevice wheelnut tightening

So you are saying the threads on wheel bolts are so short that it will not show on a tell tale untill to late, that sounds a bit of poor engineering

We had a  nearside wheel detatch from a brand new caravan just picked up from the dealer on the M1

In fifty odd years of driving, I've only been torquing wheelnuts on caravan or cars in the last five years, not having owned a wrench previously. The only time I ever had a problem was after a tyre replacement by a garage who obviously hadn't tightened the nuts properly and became evident when the steering was all over the place. I stopped and used my wheel wrench to tighten them and continued on my journey. I think we can get a bit too paranoid about this.

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It was  the one and never again Eldiss but as I was advised  by the motorway patrol the off side was also loose but the wheel rotation on the near side "assists" in studs ,if loose, undoing,it was all down to the dealers,"pre delivery "? check not being carried out, 

The Bailey problem has been sorted by fitting security studs to the wheels, but then i have since found out that other makes also had the same problem when on Alko chassis, always it seems the nearside wheels, as above probably

Since fitting tell tales on our last two Bailey caravans ,I have not used our torque wrench and we did ,just under 3000 miles towing on UK roads last year

Another "theory"put forward as to loose wheel studs is that it has been more prevelent since alloy wheels have been fitted and the different metals  steel brake  drums expanding differently ,how that pans out compaired to cars I do not know unless  caravan wheels are more suseptable to higher heat and stress when traveliing, 

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exactly, coachman has a proper wheel wrench, not one of those shorty things, lean on the wheel wrench before start of journey, job done, not sure i would know how to set a torque wrench.

"So you are saying the threads on wheel bolts are so short that it will not show on a tell tale untill to late, that sounds a bit of poor engineering"

No again I am not saying that at all.
I am saying bolts don't turn, so tell tales don't move until it is too late, in that they only self turn when the required tension is too low to stop them turning. By which time with just 5 bolts, so no spare players, it is way too late to retain the wheel firmly clamped in place.
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The short issue is separate, it is not limited to the threaded section, but the bit of every bolted together application that is elastically strained. Typically the section strained is between the underside of the head and the start of the "nut's" thread, it fits into.
Bolts just like rubber rod "stretch" [in the pre yielding sense] and it is that strain stretching that generates the clamping force that hold the wheel to the hub in our bolting application. If it did not store that clamping energy, as soon as you stopped turning the bolt the force would disappear.
Here you need to understand the wheels are clamped to the hub and it is the interplay of the clamping force and the friction between the clamped bit as the only thing holding the wheel in place normal to the bolts. Here as is almost always the case with vehicle wheels, pre, the wheel starting to come free, and moved onto the bolt shanks the bolt serves no physical retention role. It just applies that required force for the friction to do all the holding.
Where the length plays a part is in the amount of energy it can hold. Think if you had two elastic bands, one of about 3 times the length of the other. Pull each apart with the same force, then relax each by a couple of inches, you will find that the force on each is very different, the third length band will lose far more than the longer band.
Exactly the same will happen with the elastic energy in the wheel bolt, with equal levels of clamped surface settlement between the wheel and the hub. The shorter the bolt the greater the loss in its clamping force. Hence, why to best retain wheels the stretched length of the bolt is an important player, and the longer that is the higher the margin is on retaining an adequate clamping force.
It is nothing to do with “poor design” as long as the length is adequate to accommodate the settlement that could occur. Increasing the length brings increased tolerance to settlement, hence WSL marketing bolts using the age old technique of collars; they are simply safer should settlement ever occur, some always does.
Our standard bolts, as well proven, are adequate as long as we re torque as the makers mandate, so ensuring they are fully recharged with energy once any initial settlement has occurred. WSL are very much more tolerant, but I with our van don't see a need for them as I know what I should be doing.