brake dragging test
 

I suspect i have a stuck caliper in both front, and i want to do the spin wheel test. Can i jack 1 side at a time and the other on the ground or i have to lift both wheel to make it spin ? Is it ok if car its in P or it need to be in N ? And lastly is it safe to that on a 4x4 ?? i heard it can damage the 4x4 system ?

You cannot "spin" the wheels with the axles in the car - the diffs are still connected.

The easiest test is to go for a drive, them measure disk and caliper temps, using an infrared thermomter. A dragging caliper will be obvious from elevated brake temps. - compared to the other side.

If gearbox is on neutral you can spin the wheels separately. Though not very representative for testing brake drag as you are also rotating front propeller, transfer box and gearbox main axle.

ok will try that