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Adding Juice Brakes to a Model A Ford Series, Part 1

Adding Juice Brakes to a Model A Ford Series, Part 1

Story and Photos by Zac Parks

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If you're Hotrodding a Model A Ford, then adding ''Juice Brakes" is definitely on your To Do list. Of course you could just buy everything you need from one website, but what if you don't have that kind of budget? What if you want to build your car with period correct parts to the 40s, 50s and 60s? Then there is a rabbit hole of information you need to start going down and I am here to get you started.

The first thing you need to be thinking about is spindles. There are a lot of Early Ford spindles to choose from, some of which will make the job easier or harder. The Model A square back spindles are not a good option for juice brakes and even the Model A restorers will tell you that, 32 however can be made to have juice brakes with some extra steps. 
I would put the 32-36 passenger car spindles in the same category, even though there are a lot of differences between these years, they require the same extra steps to add juice brakes to them. They have a "Square Back" to them and can be commonly mistaken for other spindles. The backing plate holes are 3/8'', this being an easy way to ID them. They require opening the holes up on the baking plates to get the different bolt pattern to work, they also require a conversion that makes the backing plate hole smaller to center the brake pads in the drum and to give the correct space for the rear bearing. Messing up this step can be a really big problem. 
1937-1941 passenger car spindles, I would consider these the cream of the crop. They are the ''Round Back'' spindles and easy to spot at swap meets or when parts picking. Since Ford used these exact spindles when converting to juice brakes in 1939, you can just buy the simple brake kits and rebuild these yourself with no modifications necessary. When it comes to steering you can use its original style cross steer or make a steering bracket to keep the Model A Steering.
Then we have the 1942-1948 Spindles, they are the second series of the "Square Back" style but these came stock with juice brakes so rebuilding them and applying them to the Model A is quite easy. The backing plate holes this year are 1/2''. Their biggest problem is mistaking them for the early square back and visa versa.
All these spindles have the same inside diameter kingpin of .812, but require different length kingpin, so be sure to get the correct kingpin for the spindle you choose. But the good news is all these spindles work on the Model A I Beam. Make sure to stay tuned for next week when we talk about the rear brakes then its on to pedal options and backing plate identification! Now get back in the Garage and Get Your Shift Together!
For more on Model A Ford Hydraulic Brake Conversion click here.  
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Ivan - March 16, 2023

What about e brake

Zac Parks - February 8, 2022

Thank you Jack! I am glad I could help!

Jack Reed - February 8, 2022

Zac: Thanks for making the conversion of Ford Model A mechanical brakes to hydraulic brakes less confusing. Your videos and articles are very clear and understandable, and allow those of us who have some vintage parts stashed away to do the process mostly with what we have on hand.

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