I've completed final installation of the '71 - '78* GM 3/4 ton 4WD disk brakes on a freshly rebuilt front axle.
Follow the link in the first post to see pictures of the project at this stage.
It's taken over 18 months of fiddling around from the start of design to final install.
I can say without reservation that the roller bearing up grade is not worth the effort. I gave up when I discovered that I would have to machine the spindle to make them work. That was after installing new king pins. If you pull them, you need to find new end plugs which seem to be made of unobtanium unless you buy another king pin set.
I also ended up roaching a set of hubs installing the bearings but I'm pretty sure that was my problem, not the bearings.
The passenger side bracket fit with only minor file work. The drivers side required a trip back to the machine shop to have .050 milled off of the bracket in order to obtain the correct fit of the caliper on the rotor. The caliper should drop into the bracket and onto the rotor. The rotor should then spin with almost no drag in the caliper. There is also a clearance specification between the caliper housing and the bracket that needs attention. I left the brackets "long" and spent time with the file to get them in specification (.005 to .012).
I've started on the rear brakes and discovered that the rear drums had never been turned. (Almost makes up for all the problems on the front ones.) They've since been turned and all new shoes, springs and wheel cylinders are ready as soon as I get the cleaning done.
* Original post has the wrong year given for the parts used
Last edited by OlBlue; 07/13/2012 10:31 AM.
