67 f250 4x4 alignment help!

[Fordnut]

I have a 67 f250 4x4 with a 1978 Dana 44 front axle. A couple years ago I put all new ball joints, bearings, and switched everything to heim joints for steering. Truck drove perfect, even down the freeway at 80mph! Well I couldn’t leave well enough alone and decided to lift it.... now for my problem.
I have 4”super duty lift springs in front, and I needed to make longer shackles, so those went from 3.5” to 5.5”. I went from a skinny 32x10.5 tire to 37x13.5. Now when truck is on sitting still and you move the steering wheel the truck will drastically drop the front end depending on which way you are turning, like the steering is pulling the suspension down, and I can’t drive it over 20 mph. So here are some things I’ve tried..... I realized I changed the caster angle of axle and I feel like that’s my problem so I ordered 4* shims to go under the leafs. It didn’t change a thing, doesn’t matter if I put them forward or rear facing.
With no shims and an angle finder on bottom by the ball joint I’m at 5* positive, which I’ve read seems to be decent.
I put a drop pitman arm on, didn’t change.
I tried changing the toe in and nothing changed.

I can’t figure this thing out and it’s driving me crazy! Haha Any tips, or can you all point me in the right direction or forum to figure this thing out?!!

[two-bit]

a few thoughts.
Is the centerline of the axle still in the same place ? ie: distance from front hanger to axle tube.
The reason i ask is because i remember something about post 1980 front leafs being 36" and pre 1980 leafs being 32".
Which would move the center line of your axle back approx 2" and the rear leaf eye back approx 3'-4' inches.
You said you needed to make longer shackles ? Because the eye was to far back, or to far down ?

I saw a lot of bumpsides with '35's that had to cut the front fenders because of tire rub at full flex, on the front edge of the wheel arch, not the rear. I can't see it real clearly, but it looks like you are clearing your tires very easily with out cutting. That makes me wonder about axle position.

With out being able to put my hands on it. Kinda hard to tell. Throwing out some ideas. Worst part is, i could be completely wrong.

Two-bit

[Fordnut]

thanks for the reply. Axle moved at the most 1/2". The shackles were not long enough for the leaf eye to clear the frame so i made longer ones, maybe over did it there, could take out an inch.

So this weekend for grins I rotated my pitman arm 90, and made a new arm to see if crossover steering helped at all. Yes it did!! Still not sure why my old set up was wrong? That kind of baffles me.

So now I can actually drive truck down the road,, man those superduty lift springs are stiff!

I do still have an issue with my pitman arm not going all the way on, I have about 1/2" of spline still showing an thats as far as it will go on? i have the 1978 4 bolt box on it.