Have an esoteric question...Is there a way (other than jack up the vehicle and pull out the measuring tape) to calculate the maximum articulation of a spring set-up? I'm considering doing some suspension mods, and will need to get new shocks, and want to try and determine how much articulation will take place so I don't get the wrong shock set-up.

The basic idea is to add a shackle between the frame and the existing shackle, that bolts down for highway use, and can be freed for four wheeling. (It's similar to the tera-flex set-up, but won't pivot). I'd move the shakle hanger forward about 7.5 inches so when compressed, the stock shackle is in the right place.

I'm thinking that if I can calculate the max articulation of the leaf spring, I can add the extension of the second shackle, and get a close estimate of how much the shock needs to be able to move.

any thoughts or ideas would be greatly appreciated.

Thanks
Erik <img src="/forums/images/graemlins/cheers.gif" alt="" />

You can get a pretty good idea of the shock length by letting the springs hang at full droop. You may get another few inches of forced articulation beyond full droop, but since the shocks are inboarded to some degree, they won't extend quite as far. I suppose you could use a bottle jack at the frame to push the axle down farther for a better measurement.

How to determine shock length.

Thanks for the link Rodger. Looks like you pretty much have to ramp the truck to figure it out.

Erik <img src="/forums/images/graemlins/cheers.gif" alt="" />

If you have a ramp to use, then that is a good way, or try this, or use a pair of floor jacks at opposite corners of the truck. Even if you can't max out the suspension, you can get a good idea on shock travel by measuring at rest, then compress one corner as far as you can, measure the change in shock length and spring travel, then extrapolate to where the bumpstops would limit up-travel. Down-travel is easier, HiLift the tires off the ground for full droop and use a small bottle jack to force one side down. I run a double shackle in back (still have yet to unbolt the upper part) and have plenty of shock travel with angled 9012s in back. I made my upper shock mounts adjustable so I can fine tune the shock angle for the amount of travel, if needed.