cudak888
Well-Known Member
This isn't strictly B-body related, but it is related to slider disc brake conversions.
I bought a "mystery box" of brake calipers for my disc brake conversion, as I knew the set of calipers had a pair of FMJ 4126xxx series front calipers in the box. Score.
FMJ at center and rear, mystery calipers left and right:
Mystery caliper at left, FMJ at right:
However, the lot also included two other calipers - which are HUGE when compared to the FMJ unit. Identifying them wouldn't be that much of a problem except that the part number on them begins with "312x." From what I've read, Mopar skipped straight from 30xx to 34xx in their part number sequence, and 31xx supposedly didn't exist.
The large calipers are marked 3123 and 3124 on the cylinder end, and on the opposite side of the casting, are cast with 966-R and 967-L, respectively. My guess is that the actual part numbers are therefore 3123 966-R and 3124 967-L. I'm also guessing they're for a truck application, given that the FMJ's are already known to max out a 15" wheel when mounted on the 11.75" caliper brackets.
Not a single Google search indicates any variation of said part numbers as ever existing. However, these calipers appear to be a dead ringer for a '70s D or W-series pickup, which use the part numbers 4037-966-L and 4067-967-R.
That said: Is there anyone with a parts manual that may list what the 3123/3124 part number references to? I'm a bit wary of assuming these and the D/W series calipers are one and the same, even though common sense would dictate such.
Thanks!
-Kurt
I bought a "mystery box" of brake calipers for my disc brake conversion, as I knew the set of calipers had a pair of FMJ 4126xxx series front calipers in the box. Score.
FMJ at center and rear, mystery calipers left and right:
Mystery caliper at left, FMJ at right:
However, the lot also included two other calipers - which are HUGE when compared to the FMJ unit. Identifying them wouldn't be that much of a problem except that the part number on them begins with "312x." From what I've read, Mopar skipped straight from 30xx to 34xx in their part number sequence, and 31xx supposedly didn't exist.
The large calipers are marked 3123 and 3124 on the cylinder end, and on the opposite side of the casting, are cast with 966-R and 967-L, respectively. My guess is that the actual part numbers are therefore 3123 966-R and 3124 967-L. I'm also guessing they're for a truck application, given that the FMJ's are already known to max out a 15" wheel when mounted on the 11.75" caliper brackets.
Not a single Google search indicates any variation of said part numbers as ever existing. However, these calipers appear to be a dead ringer for a '70s D or W-series pickup, which use the part numbers 4037-966-L and 4067-967-R.
That said: Is there anyone with a parts manual that may list what the 3123/3124 part number references to? I'm a bit wary of assuming these and the D/W series calipers are one and the same, even though common sense would dictate such.
Thanks!
-Kurt
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