Carl, my cyber friend, I would like to learn what the heck that means...and I would like to know what truck this is.
I think I can see the front drivers side cab mount collapsing and the rear passenger tilting up maybe, but don't get what spring shackles have to so with it?
I do know that a leaf spring has a hard mounted hanger on one eye and a shackle on the other eye. The shackle "articulates"/rotates to allow for the increase in the springs length during flexing. So tie these things together to explain this 1/4" thing. Articulate the answer this time, buddy.
The OP included a pic of an AD cab showing the uneven gap to the frame. Whether it is a '47-'48, or a '49-'55.1, these two cab mounting systems have rear mounts which allows for substantial side-to-side leaning movement to keep the cabs from cracking from frame flex on uneven surfaces.
The '49-'55.1 had shackles with rubber bushings for rear cab mounts and were far superior in allowing the side-to-side movement. (Who said anything about "spring shackles"?)
Regardless of which year AD he has, a collapsed front cab support will cause the opposite side rear cab corner to rise.
Carl
right back atcha, friend
