My 1969 Mustang Mach I 428 Cobra Jet manual steering box broke while backing out of the garage. It made a loud "pop" noise in a hard turn and then developed a lot of steering wheel lash. The steering wheel had nearly 180 degrees of free play before it would begin to turn the front wheels.
This steering gear design is used in most of the early Mustangs and some other Ford models. Some of the cars have a long input shaft from the steering wheel, but the '69 has a short shaft with a flex coupling "rag joint" between the steering shaft and the gearbox. The gearbox is the same between manual steering and power steering cars, except for different gear ratios and preload settings. The power steering has a hydraulic cylinder attached to the steering linkage rather than internal to the steering gearbox.
It took a couple of days to remove the steering gear by removing the entire exhaust system and clutch linkage system, then wriggling the box out the bottom.
In this video, I disassemble the box to do a visual inspection to see why the gear has this much lash and to see if the steering gear box is rebuildable. It appears that it is a good box to rebuild as I found a broken bearing, but the other parts are in generally good condition.
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