As part of the rebuild I decided to fit my own axle breather kit. My Jimny has the old "hosepipe" style which was large, untidy and the hosepipes had hardened off over the years.
As we all get older things sag at the front, just ask anyone over 50! My Jimny is heavy and my old springs have worn out. However when compared to the new springs the old ones are actually longer! This is more about turns and wire diameter. The new ones have an extra turn and are made of 13mm wire compared to 11mm so I believe they will hold up rather than just compress and sag like the old ones. I can actually press the old ones by hand!
Still, there is a lot of weight up front so I decided to give the springs a fighting chance.
If you look around the internet, there is a lot of advice and conversation around castor correction for the front radius arms following a spring lift. However there is a lot less discussed about rear axle correction. Clearly "castor correction" does not apply to the rear but there is still an adverse effect due to a spring lift. There are two main effects, the nose of the differential is at the wrong angle which increases the angles the propshaft has to cope with and the spring mounts are not aligned top and bottom resulting in "banana" springs.