RUSH55
SILVER Star
Well!
I have this rather extensive backlog of memory related to this topic which involves my dealing with “death wobble” shortly after converting to Scout PS. Before the PS I’d done the Man-A-Fre shackle reversal. Made a thread on Mud in the 40/55 section. Went through EVERYTHING. Replaced all TRE’s, replaced wheel bearings, knuckle bearings (set proper preload), set toe-in, checked caster (+2 degrees or something like that, not optimal, but not enough to cause this issue) got new tires, etc.. etc... death wobble would not go away. Last resort installed a stabilizer similar to what @xtiaan2000 has here and, poof, it’s gone.
Fast forward 15 years or so and I’m reading this post by Dave G. (4+Plus) about optimal suspension geometry and how your ideal (ideal) front leaf spring setup has both eyes level, or at the same height from the ground. For several reasons he goes into depth, interestingly enough some instances of unequal heights behaving in death wobble characteristics. So out of curiosity, I measure all the solid axle leaf-sprung front ends at my place of employment, and find a few discrepancies. Pretty much every Ford had the front (hanger) higher than the rear (shackle) from the late 70’s to 2000’s.
Late 70’s Blazer, same thing. The only thing I found that had equal spring eye heights was a 4wd 1955 Chevy (NAPCO), with shackles in the front.
So I go home and check my setup. The front hangers place the front spring eye like 1-1/2” lower than the rear, totally opposite of what everything else is, and I understand why. They tried to build this kit to satisfy several things - keep axle centralized in the wheel well, maintain acceptable driveline angle, get caster, as close as possible, prevent rear hangers from having to be cut off and moved. Or maybe this was all afterthought for future versions. Either way, they failed at satisfying most of these, an my thinking is that the springs laying in a downward direction contribute more to the death wobble than almost anything else. Longer shackles in the front cause the same problem.
JMack’s Target Carrier was brought up, but remember all the work he did to his front suspension? Front shackles through the frame. His spring eyes appear to be either level, or higher in the front.
Sorry about the long winded hijack
I have this rather extensive backlog of memory related to this topic which involves my dealing with “death wobble” shortly after converting to Scout PS. Before the PS I’d done the Man-A-Fre shackle reversal. Made a thread on Mud in the 40/55 section. Went through EVERYTHING. Replaced all TRE’s, replaced wheel bearings, knuckle bearings (set proper preload), set toe-in, checked caster (+2 degrees or something like that, not optimal, but not enough to cause this issue) got new tires, etc.. etc... death wobble would not go away. Last resort installed a stabilizer similar to what @xtiaan2000 has here and, poof, it’s gone.
Fast forward 15 years or so and I’m reading this post by Dave G. (4+Plus) about optimal suspension geometry and how your ideal (ideal) front leaf spring setup has both eyes level, or at the same height from the ground. For several reasons he goes into depth, interestingly enough some instances of unequal heights behaving in death wobble characteristics. So out of curiosity, I measure all the solid axle leaf-sprung front ends at my place of employment, and find a few discrepancies. Pretty much every Ford had the front (hanger) higher than the rear (shackle) from the late 70’s to 2000’s.
Late 70’s Blazer, same thing. The only thing I found that had equal spring eye heights was a 4wd 1955 Chevy (NAPCO), with shackles in the front.
So I go home and check my setup. The front hangers place the front spring eye like 1-1/2” lower than the rear, totally opposite of what everything else is, and I understand why. They tried to build this kit to satisfy several things - keep axle centralized in the wheel well, maintain acceptable driveline angle, get caster, as close as possible, prevent rear hangers from having to be cut off and moved. Or maybe this was all afterthought for future versions. Either way, they failed at satisfying most of these, an my thinking is that the springs laying in a downward direction contribute more to the death wobble than almost anything else. Longer shackles in the front cause the same problem.
JMack’s Target Carrier was brought up, but remember all the work he did to his front suspension? Front shackles through the frame. His spring eyes appear to be either level, or higher in the front.
Sorry about the long winded hijack
