Disc Brake conversion 1966

[Francis66]

are 66 thru 68 rear axles, front drive axles, steering knuckles and hub the same

[Doc Hubler]

For drum brakes, yes, they are the same. The rear axle setup is the same in all of them as factory discs were not available on the rears, only on the front. 1966 had no front disc option for which a bad reputation, not probably deserved in my opinion, was given the Toronado, so for 67, front disc brakes were made available as an option. The set up was the same for the 68 Toro as well, but was changed for 69. Basically, the 67-68 disc brake option used a two piston caliper, while 69 onward used the more common single piston type which is still in use today. To convert to disc brakes will require special wheels that were made for cars so equipped, and there is a conversion process. This has been written about extensively. Here is the website. Note that there were additionally other improvements to the brake system starting in 67 regardless of whether the car had drum or front disc brakes. These included dual master cylinder, a "distributor" block that ran the two separate front and rear brake lines and operated a warning light if there was a brake failure in front or back, and a proportioning valve was added as well to ensure the front brakes had a slight lead on engagement before the rears to avoid rear brake lockup and handling problems with that.

http://www.breznick.com/toronado/brakes/

[Doc Hubler]

In my opinion, add a dual master cylinder setup (basically the 67 onward type), rebuilding your brakes properly, make sure you have good drums, and you'll have a safe car to drive and it will stop properly. If you plan to race the car around and think you'll have many emergency stops, especially where the brakes can't cool as easily such as the desert, then do the conversion. THe cars as designed had drum brakes that performed well for the intended application. The disc brake conversion is nice, but not necessary for ordinary driving. Some disagree with me on that, but frankly, few of the early cars had this optional equipment -- most had drums and most people didn't have problems if they were properly maintained. BTW, as you look at the website, you'll find you have to procure a lot of other parts to make the conversion work properly. The steering knuckles from a drum brake car will not work.

[bcroe]

After a million and a half miles in every kind of weather, I could tell many
stories about brakes. I would not own a car unless it had dual circuit
brakes. Drums in front will serve you well in fair weather at low speeds.
They failed miserably and dangerously for me in the 60s. How and where
will yours be driven? Bruce Roe

[Schurkey]

Basically, the 67-68 disc brake option used a two piston caliper, while 69 onward used the more common single piston type which is still in use today.

The '67--'68 calipers were 4-piston units similar to what was used on the Corvette through '83.

Expensive to make, and prone to leaks and seizing. GM started the aftermarket brake industry in response to owner complaints of Corvette and other 4-piston caliper problems.