I am about ready to start my SAS. All along I have been planning on mounting the front shackles under the frame like Jay did in this article. I built a 2 1/2 drop hanger already.

http://www.4x4wire.com/toyota/tech/mini_frontsusp1/

Lately I have read some posts indicating that it is better to go through the frame. Other than the rear of the spring being a little lower, I don't see any major difference. I would think that the dropped mount and the under the frame shackle would help with frame clearance. What do you all think?

I'm a fan of through-the-frame, simply because it allows you to build in less lift. You can always put longer shackles on to lift the truck or change the caster/pinion angle, but if you mount the shackles under the frame you're going to be limited in how much you can adjust the height of the truck.

Build in enough lift with the spring mounts to clear your steering gear, any additional height just puts the center of gravity of the truck higher than it needs to be. Move the axle forward and cut the fenders to fit whatever tire size you're aiming for.

I think going through the frame is stronger than welding the mount under especially when flexing..imho.

Either can be made as strong as the other, but you may run into steering geometry problems with the under approach - your caster will be off unless you have some serious drop spring hangers to match the shackles. Or shackles so short they will inhibit flex.

The closer you can match the factory, the easier time of it you will have. That is why I went with Brian Ellinger's kit, but there are other good ones.

have done both ways on seperate trucks,
thru is better

I put mine under the frame, used stock rear shackle hangers, set my shackle at slightly less then a 45 angle, and it seems to be happy, flexes great, and just high enough to clear 39.5's with 3" springs. -PhattieD

I coppied Jay K's SAS on project mini. the only thing I did diffrent was to put the shackle through the frame. it is a little more of a hassle in the install but the result is great. haveing less lift on the rear of the spring also point the pinion twards the Tcase flange. this is good. in my opinion it is also stronger

good luck

I have done both, and which one I would do depends on what I want from a specific truck - lift, suspension, etc. Neither is stronger than the other - it is not like you see people ripping stock rear shackle hangers off the frame or something.

i had mine under when i first did it( thought it would just be easier),but gave poor pinion angle and had to use a short shackle.then decided to go through the frame which i see being better for pinion angle and being able to use a longer shackle for better flex <img src="/forums/images/graemlins/smile.gif" alt="" />

yeah but depends on how that person can weld. if they can weld decent,yeah it will hold under the frame.but if it breaks then your screwed.as to where it goes through the frame,that helps in strength where it becomes part of the frame <img src="/forums/images/graemlins/kewl.gif" alt="" />