Gasser front axle question.

[oldblueoval]

Hello all! I see gasser front axles set up some with the shackles in the front, some in the rear. Are there pros/cons to either setup? Thanks![

 

[akatao]

I know that when you hit bump under forward movement the spring wants to travel to rear so a rear shackle is better at that, there used to be kits to do that to jeeps and scouts

 

[donsrods]

I agree with akatao on that.

Don

 

[zzrodder]

I've had 2 GM vehicles with both setups factory. Don't know if it is the rule but on my 55 Chev PU, the shackles were on the front and it had the steering box at the rear with the typical drag link going ahead to the drivers side spindle. On my 74 Blazer, it had rear shackles with the steering box in front of the axle and the drag link heading backwards to the drivers spindle.
Does it matter?? Maybe the steering geometry is more important than the shackle placement. Cross steering is common but is often subject to bump steer due to an often severe angle of the drag link due to high ride height and poor steering box location.
Someone once told me that rear shackles were preferred on 4x4's since they weren't so easily damaged on obstacles.

 

[kenny c]

I believe ZZ is on to some thing. The distance that the axle moves away from the pitman arm should be as little as possible so as to reduce bump steer. With the solid spring hanger at the same end of the spring as the steering box it should minimize that. It would also reduce bump steer if the pivot for the drag link on the pitman arm and the steering arm on the spindle (hub) were at the same height so that the drag link is as close to parallel to the ground as possible. Hope this makes sense.

 

[akatao]

I believe if the steering is in front shackles to rear and vice versa

 

[oldblueoval]

Makes sense. My 49 IH rod has shackles in the front with the steering box behind the axle and my old Dodge snow plow is the opposite, both factory setups. The Falcon will be a cross steer with a drop pitman arm.[