This repair comes to us courtesy of @ncranchero . It involves the vacuum actuator mount on many late model Ford 4WD Trucks. The affected models (in this case a 1998 F-150) will have a cast mounting tab on the axle housing that allows the actuator arm to pass through, while keeping the actuator rod in contact with the 4WD shift fork. Often, the simplest repairs are the best repairs, and in this case the simplest approach is to repair the broken part with a homemade mending plate, because replacing it means replacing the entire axle housing.

(Note: Click any image for a full size view)

	The 4WD shift fork sits in a groove in the actuator rod. Any movement of the rod other than the in-and-out that occurs during normal operation will dislodge the actuator from the shift fork. Normally, the actuator rod is held in position by the cast mount, but in this case the mount has broken.
	Here’s another look, this time with the actuator removed. Note the thickness of the cast mount.
	Cut off the jagged edge of the mount, leaving enough material to attach a mend plate. Because the placement of the mend plate is critical to proper operation of the system, grind down the surface of the existing mount to accommodate the thickness of the material you will use to make the mend plate.
	Drill and tap holes in the existing mount to allow for the attachment of the mend plate.
	Mount the rough mend plate and mark the location of the hole for the actuator arm. The hole should be drilled large enough to allow room for the bushing plus a bit of “wiggle room.”
	With the actuator mounted and the bushing in place, keep the actuator rod in contact with the shift fork using a pair of locking pliers or equivalent. This will ensure that the bushing will be placed exactly where it should be within the drilled hole. Once everything is lined up perfectly, apply JB Weld or equivalent to keep the bushing in place and allow it to dry.
	Once the adhesive has dried, remove the mend plate and weld the bushing in place permanently. Shape the plate if desired and give it a good coat of paint to prevent corrosion.
	Attach the completed mend plate to the old mount and insert the actuator rod, engaging it with the 4WD shift fork. Test for proper operation.
	This is the completed repair. Nice work! Thank you, ncranchero!

IMAGES: all images provided by @ncranchero, used with permission.