D30 Upgrade

Easier for me to do......manual and power Jeep pitman arms should be the same length.
Approx 6-3/4" center to center on the shaft holes.
These are straight, no drop, factory pitman arms.

 

Besides the spline difference there's a small length difference between Jeep manual and power pitman arms.
I can measure some various pitman arms if you need specifics....

Both manual and power arms can often be sourced from other vehicles like GM .
Doing so may allow the arm to better fit specific requirements.
Example: If a Dana 25 is installed in the Jeep the knuckle arms are shorter than those of a Dana 30.
That mean Dana 25 and Dana 30 axles will typically be best with certain length of pitman arm.
With Dana 30 axle the R/L tie rod sweep is further than Dana 25 so a longer arm may be required.

Bottom line is it get rather complicated depending on :

Particular Saginaw boxes have various ratios and various degrees of rotation.
Pitman arm spline diameter, spline count and length varies from manual to power.
Pitmans also vary concerning blind spline indexing to Saginaw shaft
Box mounted distance from tie rod effects interference between pitman arm and tie rod as axle assembly moves up and foreward.
Model of axle installed effects both sweep required and length of the knuckle arm.
Length of knuckle arms also influences the Saginaw gear ratio.

 

How wide of tires are you running? I found with the wider tires on my custom d44 front mine wandered terribly. Caster was set at 6 if I remember correctly and I didn't touch the camber. Well I finally measured and I showed 1.125 on one side and 1.375 on the other. The top of my 33's were tipped out noticeably so I finally bought and installed degree shims behind my spindles. Wow. What a difference. On pavement it finally goes straight with a little bump steer on dirt. Toe on mine it about an 1/8 also. I'm running 33 15.5 15 btw.

I measured the angle with 2 four foot levels and made marks on the ground measured this distance did some fancy trig to come up with the angles fwiw
I set the camber to zero also

 

I have not had a chance to mess with the steering yet but I did research the u joint. When I added my SM465 I had all of the u joints match, 1310 Spicer P/N U 5-760x. In my search for a new front u joint I found P/N U 5-134X for a 1976 D30.
U 5-760x 3.219" wide on both
Y 5-134x is a 1310 on one side 3.219" wide & 1330 on the other 2.625" wide.
Maybe I am over thinking this and should just run it the way it is. I hope to tear it apart and measure the diff side width.