I am working with a guy that is going to 4 link the back and 3 link the front of my samurai. It has toyota axles on it. The only thing we are stuck on right now is what spring to use. I have been told to use a ford explorer coil. anyone have any ideas. this is a budget build by the way...

use coil over springs. many many rates and lengths to choose from and easy to make mounts for. blue coil, hyper coil, eibach are some manufactures. 2.5 i.d. size seems most popular and best priced as well as huge selection.

Ok thanks...Now i know that. But what length and spring rate? I figured i would do 150lb in the back and 175lb in the front. I would prob go with 12" or so. I guess i can measure the distance between axle and frame....

I run Geo Tracker springs in the back of my SJ, they should be about 155 lb and work great.  If I was special ordering springs I would have moved the mounts up the side of the frame for more room to flex instead of placing them underneath.

175 sounds a little light for the front end though.  Stock Tracker is 450lb and 500lb.

If your buddy has a shop with a scale system you can measure the 4 corners of your rig with the axles pulled off.  That will tell you how much weight is on each corner and allow you to pick your springs accordingly.

I don't have personal experience with selecting springs for a solid axle front, but I think 175 is probably pretty close.  The tracker has such a heavy spring rate in the front because it is not just the weight of the vehicle on the axle but it it multiplied through a lever (the control arm).

If you could find some weight numbers you might try a calculator like this one: http://f-o-a.com/calculator.html

Ah, good point.  I didn't consider the effect of the IFS system on the spring rate.

I checked Rocky Road and they recommend 175 on the front as well.