The Rear axle is under the truck!
Last night my neighbor and I slid the axle under the rear leaf springs in preparation for pinion angle alignment, spring perch mounting, and shock mount alignment and install.
Needless to say I am getting very excited to finish this truck, or at least have it ready for a test drive!
I took a few photos of my wife and son. For some reason they support my sick habits... (Could be worse)
To set your rear axle you should set the leaf springs on top of the spring perches (Perches should not be welded to the axle yet). The full weight of the truck should be on the axle at this point. Slide the frame rails with a high-lift jack until an equal measurement can be achieved from the back of the brake mounting flange (On axle) to the outer edge of the spring perch. Make sure you take relative measurements on either side.
In this application I have 5 3/4" front the back of the brake mounting flange to the outer edge of the spring perch.
Now that your axle is centered between the frame rails, lift the pinion until it looks to be inline with the back of the transmission. Find a nice heavy duty nylon string and tie it to the back of the transfer case, where your drive line will be mounted to the pinion of your axle. Adjust the height of your pinion until it looks as close to direct alignment as visually possible.
Tool time. Attach an angle finder to the end of your pinion and write down this angle. Lift the front of your pinion until it is approximately 4 degrees higher than your original measurement. Once you are certain you have everything in place by re-checking all of your measurements (Including the measurements taken to center the axle) tack weld your spring perches.
*Note: it is important that your drive line is not in perfect alignment with your transfer-case. The universal joints require a slight amount of offset in order for constant universal joint rotation and equal bearing lubrication. If you obtain perfect alignment you will experience premature universal joint failure. As your tires push forward in a normal exceleration situation, the axle will torque the pinion down towards the ground. By setting the pinion angle slightly higher it will achieve perfect alignment only while under exceleration.
Shock mounts:
Now that everything is in place, you can set up your shock mounts. It is important that your shock stays in alignment at both mounting ends. What I mean by that is if you have a top mounting bolt perpendicular to the frame, the axle shock mount bolt should also be perpendicular to the frame. If you mount your shocks otherwise, you could experience binding, and ultimately shock failure.
I'm heading out to setup my axle, and will post pictures later.