Front end rebuild 1972 Duster
I should clarify some things that the newbie’s may not know. Some of this stuff I’ve known for years, other stuff I’ve just picked up over the years. If you see a mistake of mine, feel free to set me straight. I’m willing to admit fault and learn from it.
There were some changes to the suspension and steering components over the long run of the A body line. In 1973, all the A-B-E and maybe even the C body cars had some changes. Some of the changes were aimed at noise reduction and a smoother ride. The A body got revised steering linkage. The disc brake equipped cars now had the bigger and more common 5 on 4 1/2” hub pattern which matched the B-E-C body cars. I learned awhile back that while front drum brake cars were fading away, they still made them through late 1975 for the 1976 model year but….now this is just what I have read….as of January 1 1976, front disc brakes were made standard. The front drums were 10" diameter and they used a large upper ball joint though the wheel hub was the old style 4" circle.
All disc brake 1973-76 cars used the same upper ball joints as the 62-72 B and all E bodies. They also used the same lower ball joints as those cars. This is a situation where they wisely repurposed existing parts to fit other cars.
The disc and drum brake 1972 and older cars had the smaller upper ball joints and lower ball joints with a different angle to the steering arms in them. This is why when you do a drum to disc swap with 73-76 parts, the toe setting of the steering gets weird, needing adjustment.
Feel free to correct me if I missed something.