Extreme 4x4 had explained this two weeks ago. Acording to them if you mount the swing shackle in front of the spring the tire will bounce away from an object. And if you mount it rear of the spring your tire will bounce toward an object. I'm not saying this is my discovery just what they said.

1993 Chevy Suburban 2500- Tow Rig

1991 Mitsubishi Montero LS LWB

SR Parts:
Rear Axle
Coils
Trailing Arms
Front Calipers
and soon to have UCA's and idler arm.
Dual Bouncies
Air Lift Airbags
Aisins
33x12.50x15 Custom Grooved TSL's

Body lift in the near future.