You've posted this before and it's just not an issue. If you can't figure out how to dig a small hole for the jack or pull the flat tire forward onto a rock to make room, what are you doing offroad?
I understand your point but you are not always offroad and its not always you when a jack is needed. If it your wife or you are on tarmac your solution is useless. The adapter was created by my wife because centering a post jack where the factory recommends is not the safest or the easiest for many. Im not the least concerned for my self as I can survive but when my wife/daughter is traveling to Mexico as she frequently does I want to provide her with something she is comfortable with that works and is safe. Factory mechanical jack ( at least with Toyota) is an extremely reliable jack. Hate on the adapter all you want but it makes jacking safer and easier even for someone like you that feels they have it all figured out, it a safety product that works for a fraction of the cost of a Safe Jack.
Understood. That makes sense.
Yep, but they aren't big enough. You need two maybe for a level lift on the OP projected weight, and then how much safety factor does that come with? Add in a slope, or some wobble during lift to unequally load a pair? Maybe you need three?!? The ones I linked to were/are the only ones I've come across second hand that one would actually be up to the job of lifting a 9 ton axle. If you are lifting that much weight on a big squishy bag you won't perhaps be pushing on the axle to start with, it may push on the sump and steering gear etc, so I think the bigger the better to spread it out. But unless you buy new from a specialist for lots of cash those yellow ones were the only ones I could find, which packed up were indeed too big. As well as the flat one I mentioned before I did buy a pair from that same link that do 5 tons each, the storage bag for them both, the hose and the control box is nudging three feet diameter and maybe 10" deep.
A 12k lb rated jack is big enough to lift a 7k lb axle OP is talking about under any type of surface condition. Going directly under the axle or control arm in case it's a IFS will provide the highest lift. Unless we're talking about a specific vehicle it's hard to know whether a particular Jack will work. But using bags meant to right a rolled truck or forklift to change a tire is, IMO, unnecessary.
This is a great idea.
Sorry, my brain is confusing two threads
In my case I do have maybe 9 tons on the front axle, and the yellow bags I pictured are the only things without going new that would lift it with one bag. Yes too big but best second hand option I could find. And at that size I would think I might end up bending steering etc. But not really what the OP was asking. Sorry, I should pay more attention. I'll shut up now!No dislike of the Safe Jack just educating the limits and giving cost effective options.
X2.