Article 968 - Four Pinion Differential Assembly - 9" Diameter Ring Gear Axle

TSB #56 - December 16, 1966
(1966 Fairlane GT and GT/A)

A new four pinion differential assembly has been released for the 1966 model Fairlane GT and GT/A. This change was effective in axle production April 15, 1966, and included both the conventional and limited slip axle assemblies. This new four pinion differential assembly is more durable than the two pinion assembly formerly installed on such vehicles. It has also been installed on the 1967 models.

When complaints of axle problems are encountered on affected models built prior to April 15, 1966, the axle should be inspected for evidence of pinion gear damage. If such damage has occurred, the axle should be rebuilt incorporating the four pinion differential components.

The following parts, in addition to those necessary to make a general repair, are required to convert to the four pinion assembly.

C2AZ-4204-KDifferential case (conventional)A
C2AZ-4204-LDifferential case (limited slip)C
C1AZ-4211-APinion shaft kitB

NOTE: When rebuilding a two pinion assembly to incorporate the four pinion components, it will be necessary to order four (4) new pinion gears (4215) for that application.

Oper: Use published suggested labor time schedule