What angle should your shackles be on when the suspension is at full droop. Take the rear as an example. Should the shackle be perpendictular to the chassis, angled towards the rear of the jeep or angled towards the spring or front of the jeep?
Thanks.......

Originally posted by the TJ kid
What angle should your shackles be on when the suspension is at full droop. Take the rear as an example. Should the shackle be perpendictular to the chassis, angled towards the rear of the jeep or angled towards the spring or front of the jeep?
Thanks.......

If there is nothing limiting droop then your shackle will pull to an angle similar to the portion of the spring just before the eye. Kind of like continuing the arc.

Nomesane:D

What BigDude said.(as a general rule).
But the question is where does the shackle sit when it is in its neutral position(with no compresion or droop).
If your shackle is angled away from the spring, it will allow more downward travel due to the fact that it can fall away from the frame in an arch towards the axle, with almost no resistance. This is good for travel, but it is also prone to cause wheel hop, under hard exceleration because their is little force to keep the axle planted to the ground.
If the shackles are straight up and down there is less droop due to the fact that you will only droop as far as springs wiill fan out, plus a little extension from the shackles swinging towards the axle. This is a lot more stable though on excelerated climbs due to the fact that there is less allowable unrestricted up and down movement of the shackle(basicly no unrestricted drop of the shackle).
If the shackles are angled in towards the spring, there is less droop than with the angled away position due to the fact that the shackles can only droop untill the tension of spring flex pulls it in a straight line with the fanned out spring pack. Angled inward towards the springs is still prone to wheel hop because under exceleration the shackle will fold upward fairly easily towards the frame and still be allowed to freely fall away from the frame,(although it is less prone to hop than than the angled away configuration).
I like to run my front shackles angled away to allow as much droop as possible, but I keep my rear shackles fairly close to straight up and down to keep the rear axle planted well durring full launch, hard throttled climbs.
From all of the experimenting I have done over the years, this set up, works the best for me. My rig is stronger, and hooks up, with more power on steep climbs, than with any other configuration I have tried

i noticed with my front shackles angled away from the springs, that it would let the front raise up during climbs which helps weight transfer(traction). i use stiff rear srings(52" long GM 1/2 ton) so i angled the shackles away from the springs to gain droop and haven't had the hop problems. with softer springs, i can vouche for the hop(and axle wrap).:beer:

Thanks guys. Excellent explanation H8 now I understand!