I beg to differ. No-one should be worried about overloading the jack (and who cares about breaking a $30 scissor jack, anyway), but your trailer frame is not designed to be supported from the corners - hold it up on the jacks alone and the frame is very likely to bend.
That's why you never want to use the stabilizer jacks for changing a wheel. (Not because you might break the jack!)
Well, you might have a point. However, evidence to the contrary does not support that concern.
If such were the case, supporting the unit only by the tongue jack would place enormous strain on a much longer moment arm, axle(s) to hitch, than would any other point on the frame.
In this case, the entire weight of the forward frame rests on a single point, with lengthy bending forces at work. I'm not aware anyone ever has reported a frame bending from that application in a static, parked situation.
Additionally, the same situation exists to a much greater degree when towing, and is exacerbated by continuous frame flexing due to road conditions and pitching motion in general. This belies a concern that frame damage could occur from applying forces greater than mere stabilization to a corner.
Notably, the Jayco owner's manual I have says this about stabilizer jacks:
WARNING
DO NOT USE THE STABILIZER JACKS TO LEVEL THE RV. It is important
to remember that the stabilizer jacks are to be used only for support while occupying and moving around the RV. They are not designed to support the weight of the RV. (emphasis mine)
Now, any person researching jack specifications knows the last sentence to be utterly and completely false as mechanical strength is not at issue. I suggest this is a liability dodge by Jacyo rather than an engineering concern. Notice that the warning applies only to the jack, not to the frame (and thus not to any potential damage to the frame). The clear message that we are to accept is that a jack will be damaged, nothing else is implied (and Jayco leaves little to the imagination about things they don't approve of).
Were it otherwise, Jayco would have included a specific point about that, as they do for numerous other things involving freezing, animal/insect damage, wind damage, etc., etc.
I am not advocating using a stabilizer to level. Using them to substantially level a unit (say beyond a half bubble or so) indicates a lack of understanding about how to get a unit reasonably level while initially parking it.
