Contour Enthusiasts Group Archives Forums Modifications Suspension Official Ford preloading how to??

No, do not loosen the ones on the subframe. Only those bolts where the control arms connect to the wheel hub assembly.
There should be 3 total per side.

Assuming the back of the car is up on jackstands with the wheels about one inch off the ground (front not necessary to be off the ground):
Put a small floorjack under the lowest point of the control arm and jack up the wheel/hub until it is sitting about the right height in the wheel well. Wheels can be off for this and you can get to the bolts easier.

There is one bolt and a big washer on the rear control arm. Loosen this one, let the bushing relax (happens as soon as the bolt loosens) then retighten it.
The trailing arm (I think its called that) has the bolt that goes through a u-bracket. It is also the lowest part of the hub assembly. Loosen this then retighten.
The front control arm (the one with the rubber pieces in it) is bolted through the control arm with a bolt and a nut. Loosen these, retighten.

Thats it. If there was tension in the bushing you can see it turn when the torque is released.