Topic: Boss and Big Suspension Spindles

[J_Speegle]

The subject came up again on another site so thought I would post a picture I posted to that thread showing the two versions of the spindle ID markings. Depending on when the car was built it may have had one of each or both of one version or the other. For the complete engineering number for the DO version on the right you have to include all the letters and numbers all the way through the last/lowest letter. In this case "B" for D0ZA-3108-B

[J_Speegle]

In addition to the paint marks used by the line workers for quick identification Ford added a short section of baling with wrapped twice around the upper upright of the spindle as shown in the picture below. There were some problems with the initial introduction of these new spindles that created some issues and I guess the wrap was one of the ways to call attention to the different part

[J_Speegle]

The following is a letter sent to owners of 69 Mustang and Cougar owners with disc brakes stating about the possibility of the wrong hubs and rotors being installed. This may have been connected with the introduction of the new "big suspension) with the different spindles, rotor hubs, bearings and so on.  Have, what I believe to be a longer and more in dept document from Ford for service and dealership people I will scan and post with allot more details information

[J_Speegle]

Two additional documents are posted in one pdf found in the Library under 1969 and then down towards the bottom under the Special Service Letters, Service Campaign Documention and Recalls section. It talks about an issue they had at some or all plants where the newly introduced larger bearing rotors mistakenly got installed on the standard spindles and how dealers should address the issue. Second part of the document (last four pages) describes how to inspect a Boss 302 (or really any car equipped with the new heavy duty spindles, bearings and rotors) for the right parts and how to address the issues if the findings are different than expected.

Last diagram shows the spindles were identified in the document as having blue paint  on the steering arm of the spindle. On original cars a medium blue has been documented many times and a few with a more teal coloration also.


Titled -

69 Disc Brake Spindle and/or Hub and Rotor Mismatch
Campaign #668 (Ford of Canada)  Letter- July 11, 1969