Posted by Alan Bowes on January 04, 1998 at 18:36:46:
In Reply to: shackle reversal posted by Dave Lundstrom on January 04, 1998 at 14:34:05:
As mentioned, the shackles on an M37 are set up with the fixed shackle at the front and the hinged shackle at the rear. Whether one setup is better than the other in general terms is not the real issue here. Any change that affects the geometry of the wheel alignment, suspension, and steering should be approached with caution. The effect of switching these will vary from vehicle to vehicle. I'm not saying that factory-designed suspension systems can't be improved upon, although it seems that about 9 out of 10 such alterations end up making things worse instead of better. Caster is one parameter of particular concern here...not just static caster, but how it's affected during braking or cornering. One effect of switching the fixed and hinge shackles is supposed to be on the type of deformation of the leaf spring when a wheel strikes an object or irregularity while moving in a forward direction. With a hinged fron shackle, there is a tendency for a stiffer shock reaction and a little more tendency for the front of the vehicle to lift. On the other hand, it may slightly increase the tendency to bottom out the spring. Frankly, I think you'd find any ride advantages negligible and you may pay a penalty in terms of altered wheel alignment and handling. But if this area really interests you, it may be worth some research. Who knows? Maybe it will be one of those 1-in-10 cases where it actually helps.
Regards,
Alan
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