A new project rolls into the shop. It is a simple task. A 65 Mustang that needs the rear drum brakes changed over to disc brakes. Simple, easy and painless.
NO! No it’s not…
Project cars can be easy, but not without complications. Many jobs on older project cars and trucks can go smooth, but… Some times they have a mind of there own.
Things that cause the most issues are parts availability and the quality of the parts available. This 65 Mustang is on upgrade #6 a rear drum to disc conversion. The after market brake kits have a wide range of prices. Price is related to the overall quality of the parts in the kit.

Little red 65 Mustang.
1st: Take it apart and see if the axle shafts will be ok to be used with disc brakes.

Old drum brakes with axle in place
Too much runout at the flange will require new axles to be installed. Yep, they are bent. 🙁 A dial indicator is used to confirm that they are bent.

Taking a runout reading on a brake rotor.
2nd: After replacing the axle shafts, new bearings and seals. Plus a dry fit check of all brackets it was time to do the final machine work on the rotor with the new axles. Even with new axles, the flange still has a small amount of runout, but it was way better than the old bent axles. Below is a video for an on the car machine I use to machine the rotor true to the axle flange.

On the car rotor turning machine, used to cut the surface of the brake rotor bringing the surface true to the axle flange.
3rd: Once the rotor is machined all the remaining parts can be installed. Bleed the brake system, check for leaks and test drive for normal operation.

Caliper installed on ford 8 inch differential. Parking brake cables installed.

Rotor, caliper and spacer installed. Almost ready to bleed the brakes.
The instructions stated that the average working time was 3.5 hours. NOT! Actual working time was over 8 hours and 4 delays for parts that did not fit or needed to be fitted to the car.
No, the job did not go smooth. The job was finished and it worked correctly, but… It needed more. More vacuum boost. The boosters job is to help you push your brakes. It adds assist to the foot pressure you are applying.

Master cylinder and 9 inch booster.
So, even though the brakes worked good. The effort to stop the car needed an upgrade.
A bigger 9 inch booster and a over boar 1.25″ inch master cylinder plus 6 more hours of labor did the trick. New lines and bleed out the brakes again! Test drive and check for leaks one more time.
Done.

TSC Logo – Tony’s Service Center Phoenix, AZ 85016


working on the car.

