Fair point about the springs, check the rear brake lines between the body and the chassis, especially above the cross member above the rear axle. They do give up in that areaI don't want to talk about the reliability issue that has been talked about a lot in every part of the planet. I found the car converted to coil springs and I will leave it like that because I don't like air suspensions, I never liked them on motorcycles, bicycles and cars. On motorcycles and bicycles they work at higher pressures and have a strange progression, from the spring you always know what to expect, I have always replaced the air suspensions with coil springs, and so have many of my friends who raced. In motocross the high quality suspensions are coil springs. In cars it is different because the air cushions have a large volume and work at lower pressures so they are more comfortable than the coil springs as well as having the advantage of having adjustable height, in my opinion useful on a cargo vehicle. The disadvantage is a greater roll and the "boat" effect that make the driving very filtered, in my opinion the coil springs make the driving more sincere and predictable. of all the cars with air suspensions that I have tried I appreciated the comfort but not the driving, they adapt to many situations but do not excel in anything. I respect those who use the EAS but I have never thought of removing the springs but probably in the future I will use a more braking hydraulics and remove the rear anti-roll bar to recover some travel, as I also did in the Nissan Terrano. The biggest problem I have now is with the brakes, after changing the caliper pistons, the oil and having bled the brakes twice in a row following the RAVE, I have little braking power on the front right wheel, I am thinking of a leak, the modulator, or some brake lines that need changing...

As for a front brake différence, the calipers may just be passed their use date. I have a tool at the garage that reads brake line pressures, it was really useful diagnosing a failed recon caliper after 6 months for a client after the van sat for a while unused after the repair

Rebuilding your calipers can be hit and miss sometimes, although many have had successfully done so. I'd rather replace for factory recon units and certainly wouldn't take a chance rebuilding them on a clients car for guarantee reasons
