3/4 ton front disc brakes

["Allan Weidenheimer" <allanw@domain.elided>]

Anyone interested in 3/4ton (8 bolt) front discs, read on,
otherwise you can skip ahead ;)
Research from my 1989 Bendix catalog:
A 74/75 200 with front discs and 12x3 rears calls for
D149 pads, 11758 master cyl, and R55103 and R55102
rebuilt calipers.  The same fig, but with 12x2-1/2 rears
calls for different parts.

Chevy seems to be a poor match, they either list 11"
or 13" rear brakes.
Ford only shows 12x2-1/2 rears, and the pad/caliper/
mc part numbers are all different.
Dodge, on the other hand, lines up pretty good:
75-77 W250/W200 4WD 3/4 ton with 4.5M front
axle calls for D149 pads, 11758 master cyl, but
R55159 and R55158 calipers.  This app has
12x2-1/2 rear brakes, but the same parts are listed
for '78, which had 12x3 rears.  The Dodges use
smaller rear wheel cylinders than IHC though.

I was hoping to find a matching application, where I could
get the knuckle out parts, master cylinder, and proportioning
valve.  However, due to the different rear wheel cylinder
sizes, I'm not sure that the proportioning valve would be
right.  It appears that Dodge 4WD pickups started getting discs
in '75.  Of course, Dodge isn't much more common than IHC
in wrecking yards...

Allan Weidenheimer
72 1210 Pickup