Jackup

How much weight do you anticipate you'll need to lift?

Assume large 4 x 4 laden to the gills = 3.5 t (your Sherman Tank)- but you only need to lift some of that. Add a margin for ease of use & decent working limit - a 4 tonne jack looks like it may do the job.

At Supercrap (or similar auto store) they will have a bottle jack (aka hydraulic jack) that will lift 4 tonne.

How high do you anticipate you will need to lift?

e.g. flat tyre on 265/75 x 16 " will drop say 200mm.
so you'll need to lift 200 mm
+ say 40 mm to enable easy removal of tyre
+ suspension travel - say 400mm
= 640 mm

Here is an example. They are not actual measurements because I have not nicked into the store/out to the fourby to check the measurements. But this is an example, so that you will see what I am getting at.

Let's look at a 'typical' 4 t jack. The specs say it will raise to 486mm. Therefore although it 'appears' to do the job, it won't lift in one single attempt to change that tyre.

Look at a 8 t jack - heaps more capacity for lift - it says 580 mm. Still not enough to do the job in one lift procedure. A 10 t jack is starting to be very heavy & cumbersome, won't meet your space limits, so we'll stick with the 8 t jobbie.

Maybe you need some other aids to help this 8 t bottle jack do the job.
Bottle jack aids: hardwood block of say 100 x 100 x 100 mm height; 300 x 300x 30 mm thick - 10 ply jacking plate to stop jack disappearing into the sand/mud etc; handle extension so you are not under the vehicle while lifting/changing spare.

There, job done - you required 640 mm lift; this solution provides (jack 580 mm+ plate 30mm + block 100mm) 710mm = 70 mm "spare" = bugger all spare lifting height, really.

BUT have you considered you may need another type of jack?

e.g.
Exhaust jack
Hi Lift jack.
I reckon there will be plenty of threads if you search for same here on EO.

I use a high lift as I have fabricated mounts front & rear to facilitate same. It's quick, simple & easy, but make sure you don't let the vehicle fall off the high lift! Used to do the above example for years (better than screw jack that was standard with vehicle), and I still carry it. Only take the exhaust jack if going in beach conditions as High lift & bottle jacks disappear into the sand , even with a jacking plate.

Horses for courses, T-Rib.

cheers

I use a hydraulic bottle jack. If when you get a flat, the axle etc is too low (or the jack is too tall) to get the jack under, drive the flat wheel up onto a rock or log enough to gain clearance. Old bush trick.

Following on from my last post - the reason I went for the larger bottle jack was
because it may be useful to help lift a fully loaded BIG 4WD in trouble somewhere.
Anyhow, was thinking about the comments regarding changing a wheel in sand.
I have a fold-out plastic "cross" that holds up the sag in my camper-trailer awning.
It is spring loaded and held up in position by a 9' tent pole. Only use it when there
is a threat of rain. I wonder how a jack base using this idea would work in sand.
Sketching it out, two pieces of timber 600mm long, 200mm wide and about 40mm thick in
the shape of a cross, rebating by width so the two pieces fit flush across each
other. On top of that would go another piece of timber 200x200 in the centre of the cross for the jack base to sit on and provide support. The theory is that the load would be spread out further than one solid block. Dunno whether it would work but I'm interested enough to make one up and try it out (preferably on someone elses rig !)

cheers
T-Rib